IntroductionCase study research excels at bringing us to an understanding of a complex issue or object and can extend experience or add strength to what is already known through previous research. Case studies emphasize detailed contextual analysis of a limited number of events or conditions and their relationships. Researchers have used the case study research method for many years across a variety of disciplines. Social scientists, in particular, have made wide use of this qualitative research method to examine contemporary real-life situations and provide the basis for the application of ideas and extension of methods. Researcher Robert K. Yin defines the case study research method as an empirical inquiry that investigates a contemporary phenomenon within its real-life context; when the boundaries between phenomenon and context are not clearly evident; and in which multiple sources of evidence are used (Yin, 1984, p. 23).
Critics of the case study method believe that the study of a small number of cases can offer no grounds for establishing reliability or generality of findings. Others feel that the intense exposure to study of the case biases the findings. Some dismiss case study research as useful only as an exploratory tool. Yet researchers continue to use the case study research method with success in carefully planned and crafted studies of real-life situations, issues, and problems. Reports on case studies from many disciplines are widely available in the literature.
This paper explains how to use the case study method and then applies the method to an example case study project designed to examine how one set of users, non-profit organizations, make use of an electronic community network. The study examines the issue of whether or not the electronic community network is beneficial in some way to non-profit organizations and what those benefits might be.
Many well-known case study researchers such as Robert E. Stake, Helen Simons, and Robert K. Yin have written about case study research and suggested techniques for organizing and conducting the research successfully. This introduction to case study research draws upon their work and proposes six steps that should be used:
- Determine and define the research questions
- Select the cases and determine data gathering and analysis techniques
- Prepare to collect the data
- Collect data in the field
- Evaluate and analyze the data
- Prepare the report
The first step in case study research is to establish a firm research focus to which the researcher can refer over the course of study of a complex phenomenon or object. The researcher establishes the focus of the study by forming questions about the situation or problem to be studied and determining a purpose for the study. The research object in a case study is often a program, an entity, a person, or a group of people. Each object is likely to be intricately connected to political, social, historical, and personal issues, providing wide ranging possibilities for questions and adding complexity to the case study. The researcher investigates the object of the case study in depth using a variety of data gathering methods to produce evidence that leads to understanding of the case and answers the research questions.
Case study research generally answers one or more questions which begin with "how" or "why." The questions are targeted to a limited number of events or conditions and their inter-relationships. To assist in targeting and formulating the questions, researchers conduct a literature review. This review establishes what research has been previously conducted and leads to refined, insightful questions about the problem. Careful definition of the questions at the start pinpoints where to look for evidence and helps determine the methods of analysis to be used in the study. The literature review, definition of the purpose of the case study, and early determination of the potential audience for the final report guide how the study will be designed, conducted, and publicly reported.
Step 2. Select the Cases and Determine Data Gathering and Analysis Techniques
During the design phase of case study research, the researcher determines what approaches to use in selecting single or multiple real-life cases to examine in depth and which instruments and data gathering approaches to use. When using multiple cases, each case is treated as a single case. Each case�s conclusions can then be used as information contributing to the whole study, but each case remains a single case. Exemplary case studies carefully select cases and carefully examine the choices available from among many research tools available in order to increase the validity of the study. Careful discrimination at the point of selection also helps erect boundaries around the case.
The researcher must determine whether to study cases which are unique in some way or cases which are considered typical and may also select cases to represent a variety of geographic regions, a variety of size parameters, or other parameters. A useful step in the selection process is to repeatedly refer back to the purpose of the study in order to focus attention on where to look for cases and evidence that will satisfy the purpose of the study and answer the research questions posed. Selecting multiple or single cases is a key element, but a case study can include more than one unit of embedded analysis. For example, a case study may involve study of a single industry and a firm participating in that industry. This type of case study involves two levels of analysis and increases the complexity and amount of data to be gathered and analyzed.
A key strength of the case study method involves using multiple sources and techniques in the data gathering process. The researcher determines in advance what evidence to gather and what analysis techniques to use with the data to answer the research questions. Data gathered is normally largely qualitative, but it may also be quantitative. Tools to collect data can include surveys, interviews, documentation review, observation, and even the collection of physical artifacts.
The researcher must use the designated data gathering tools systematically and properly in collecting the evidence. Throughout the design phase, researchers must ensure that the study is well constructed to ensure construct validity, internal validity, external validity, and reliability. Construct validity requires the researcher to use the correct measures for the concepts being studied. Internal validity (especially important with explanatory or causal studies) demonstrates that certain conditions lead to other conditions and requires the use of multiple pieces of evidence from multiple sources to uncover convergent lines of inquiry. The researcher strives to establish a chain of evidence forward and backward. External validity reflects whether or not findings are generalizable beyond the immediate case or cases; the more variations in places, people, and procedures a case study can withstand and still yield the same findings, the more external validity. Techniques such as cross-case examination and within-case examination along with literature review helps ensure external validity. Reliability refers to the stability, accuracy, and precision of measurement. Exemplary case study design ensures that the procedures used are well documented and can be repeated with the same results over and over again.
Step 3. Prepare to Collect the Data
Because case study research generates a large amount of data from multiple sources, systematic organization of the data is important to prevent the researcher from becoming overwhelmed by the amount of data and to prevent the researcher from losing sight of the original research purpose and questions. Advance preparation assists in handling large amounts of data in a documented and systematic fashion. Researchers prepare databases to assist with categorizing, sorting, storing, and retrieving data for analysis.
Exemplary case studies prepare good training programs for investigators, establish clear protocols and procedures in advance of investigator field work, and conduct a pilot study in advance of moving into the field in order to remove obvious barriers and problems. The investigator training program covers the basic concepts of the study, terminology, processes, and methods, and teaches investigators how to properly apply the techniques being used in the study. The program also trains investigators to understand how the gathering of data using multiple techniques strengthens the study by providing opportunities for triangulation during the analysis phase of the study. The program covers protocols for case study research, including time deadlines, formats for narrative reporting and field notes, guidelines for collection of documents, and guidelines for field procedures to be used. Investigators need to be good listeners who can hear exactly the words being used by those interviewed. Qualifications for investigators also include being able to ask good questions and interpret answers. Good investigators review documents looking for facts, but also read between the lines and pursue collaborative evidence elsewhere when that seems appropriate. Investigators need to be flexible in real-life situations and not feel threatened by unexpected change, missed appointments, or lack of office space. Investigators need to understand the purpose of the study and grasp the issues and must be open to contrary findings. Investigators must also be aware that they are going into the world of real human beings who may be threatened or unsure of what the case study will bring.
After investigators are trained, the final advance preparation step is to select a pilot site and conduct a pilot test using each data gathering method so that problematic areas can be uncovered and corrected. Researchers need to anticipate key problems and events, identify key people, prepare letters of introduction, establish rules for confidentiality, and actively seek opportunities to revisit and revise the research design in order to address and add to the original set of research questions.
4. Collect Data in the Field
The researcher must collect and store multiple sources of evidence comprehensively and systematically, in formats that can be referenced and sorted so that converging lines of inquiry and patterns can be uncovered. Researchers carefully observe the object of the case study and identify causal factors associated with the observed phenomenon. Renegotiation of arrangements with the objects of the study or addition of questions to interviews may be necessary as the study progresses. Case study research is flexible, but when changes are made, they are documented systematically.
Exemplary case studies use field notes and databases to categorize and reference data so that it is readily available for subsequent reinterpretation. Field notes record feelings and intuitive hunches, pose questions, and document the work in progress. They record testimonies, stories, and illustrations which can be used in later reports. They may warn of impending bias because of the detailed exposure of the client to special attention, or give an early signal that a pattern is emerging. They assist in determining whether or not the inquiry needs to be reformulated or redefined based on what is being observed. Field notes should be kept separate from the data being collected and stored for analysis.
Maintaining the relationship between the issue and the evidence is mandatory. The researcher may enter some data into a database and physically store other data, but the researcher documents, classifies, and cross-references all evidence so that it can be efficiently recalled for sorting and examination over the course of the study.
Step 5. Evaluate and Analyze the Data
The researcher examines raw data using many interpretations in order to find linkages between the research object and the outcomes with reference to the original research questions. Throughout the evaluation and analysis process, the researcher remains open to new opportunities and insights. The case study method, with its use of multiple data collection methods and analysis techniques, provides researchers with opportunities to triangulate data in order to strengthen the research findings and conclusions.
The tactics used in analysis force researchers to move beyond initial impressions to improve the likelihood of accurate and reliable findings. Exemplary case studies will deliberately sort the data in many different ways to expose or create new insights and will deliberately look for conflicting data to disconfirm the analysis. Researchers categorize, tabulate, and recombine data to address the initial propositions or purpose of the study, and conduct cross-checks of facts and discrepancies in accounts. Focused, short, repeat interviews may be necessary to gather additional data to verify key observations or check a fact.
Specific techniques include placing information into arrays, creating matrices of categories, creating flow charts or other displays, and tabulating frequency of events. Researchers use the quantitative data that has been collected to corroborate and support the qualitative data which is most useful for understanding the rationale or theory underlying relationships. Another technique is to use multiple investigators to gain the advantage provided when a variety of perspectives and insights examine the data and the patterns. When the multiple observations converge, confidence in the findings increases. Conflicting perceptions, on the other hand, cause the researchers to pry more deeply.
Another technique, the cross-case search for patterns, keeps investigators from reaching premature conclusions by requiring that investigators look at the data in many different ways. Cross-case analysis divides the data by type across all cases investigated. One researcher then examines the data of that type thoroughly. When a pattern from one data type is corroborated by the evidence from another, the finding is stronger. When evidence conflicts, deeper probing of the differences is necessary to identify the cause or source of conflict. In all cases, the researcher treats the evidence fairly to produce analytic conclusions answering the original "how" and "why" research questions.
Step 6. Prepare the report
Exemplary case studies report the data in a way that transforms a complex issue into one that can be understood, allowing the reader to question and examine the study and reach an understanding independent of the researcher. The goal of the written report is to portray a complex problem in a way that conveys a vicarious experience to the reader. Case studies present data in very publicly accessible ways and may lead the reader to apply the experience in his or her own real-life situation. Researchers pay particular attention to displaying sufficient evidence to gain the reader�s confidence that all avenues have been explored, clearly communicating the boundaries of the case, and giving special attention to conflicting propositions.
Techniques for composing the report can include handling each case as a separate chapter or treating the case as a chronological recounting. Some researchers report the case study as a story. During the report preparation process, researchers critically examine the document looking for ways the report is incomplete. The researcher uses representative audience groups to review and comment on the draft document. Based on the comments, the researcher rewrites and makes revisions. Some case study researchers suggest that the document review audience include a journalist and some suggest that the documents should be reviewed by the participants in the study.
Applying the Case Study Method to an Electronic Community NetworkBy way of example, we apply these six steps to an example study of multiple participants in an electronic community network. All participants are non-profit organizations which have chosen an electronic community network on the World Wide Web as a method of delivering information to the public. The case study method is applicable to this set of users because it can be used to examine the issue of whether or not the electronic community network is beneficial in some way to the organization and what those benefits might be.
Step 1. Determine and Define the Research Questions
In general, electronic community networks have three distinct types of users, each one a good candidate for case study research. The three groups of users include people around the world who use the electronic community network, the non-profit organizations using the electronic community network to provide information to potential users of their services, and the "community" that forms as the result of interacting with other participants on the electronic community network.
In this case, the researcher is primarily interested in determining whether or not the electronic community network is beneficial in some way to non-profit organization participants. The researcher begins with a review of the literature to determine what prior studies have determined about this issue and uses the literature to define the following questions for the study of the non-profit organizations providing information to the electronic community network:
Why do non-profit organization participants use the network?
How do non-profit organization participants determine what to place on the electronic community network?
Do the non-profit organization participants believe the community network serves a useful purpose in furthering their mission? How?
Step 2. Select the Cases and Determine Data Gathering and Analysis Techniques
Many communities have constructed electronic community networks on the World Wide Web. At the outset of the design phase, the researcher determines that only one of these networks will be studied and further sets the study boundaries to include only some of the non-profit organizations represented on that one network. The researcher contacts the Board of Directors of the community network, who are open to the idea of the case study. The researcher also gathers computer generated log data from the network and, using this data, determines that an in-depth study of representative organizations from four categories -- health care, environmental, education, and religious -- is feasible. The investigator applies additional selection criteria so that an urban-based and a rural-based non-profit are represented in the study in order to examine whether urban non-profits perceive more benefits from community networks than rural organizations.
The researcher considers multiple sources of data for this study and selects document examination, the gathering and study of organizational documents such as administrative reports, agendas, letters, minutes, and news clippings for each of the organizations. In this case, the investigator decides to also conduct open-ended interviews with key members of each organization using a check-list to guide interviewers during the interview process so that uniformity and consistency can be assured in the data, which could include facts, opinions, and unexpected insights. In this case study, the researcher cannot employ direct observation as a tool because some of the organizations involved have no office and meet infrequently to conduct business directly related to the electronic community network. The researcher instead decides to survey all Board members of the selected organizations using a questionnaire as a third data gathering tool. Within-case and cross-case analysis of data are selected as analysis techniques.
Step 3. Prepare to Collect the Data
The researcher prepares to collect data by first contacting each organization to be studied to gain their cooperation, explain the purpose of the study, and assemble key contact information. Since data to be collected and examined includes organizational documents, the researcher states his intent to request copies of these documents, and plans for storage, classification, and retrieval of these items, as well as the interview and survey data. The researcher develops a formal investigator training program to include seminar topics on non-profit organizations and their structures in each of the four categories selected for this study. The training program also includes practice sessions in conducting open-ended interviews and documenting sources, suggested field notes formats, and a detailed explanation of the purpose of the case study. The researcher selects a fifth case as a pilot case, and the investigators apply the data gathering tools to the pilot case to determine whether the planned timeline is feasible and whether or not the interview and survey questions are appropriate and effective. Based on the results of the pilot, the researcher makes adjustments and assigns investigators particular cases which become their area of expertise in the evaluation and analysis of the data.
Step 4. Collect Data in the Field
Investigators first arrange to visit with the Board of Directors of each non-profit organization as a group and ask for copies of the organization�s mission, news clippings, brochures, and any other written material describing the organization and its purpose. The investigator reviews the purpose of the study with the entire Board, schedules individual interview times with as many Board members as can cooperate, confirms key contact data, and requests that all Board members respond to the written survey which will be mailed later.
Investigators take written notes during the interview and record field notes after the interview is completed. The interviews, although open-ended, are structured around the research questions defined at the start of the case study.
Research Question: Why do non-profit organization participants use the network?
Interview Questions: How did the organization make the decision to place data on the World Wide Web community network? What need was the organization hoping to fulfill?
Research Question: How do non-profit organization participants determine what to place on the electronic community network?
Interview Questions: What process was used to select the information that would be used on the network? How is the information kept up to date?
Research Question: Do the non-profit organization participants believe the community network serves a useful purpose in furthering their mission? How?
Interview Questions: How does the organization know if the electronic community network is beneficial to the organization? How does the electronic community network further the mission of the organization? What systematic tracking mechanisms exist to determine how many or what types of users are accessing the organization information?
The investigator�s field notes record impressions and questions that might assist with the interpretation of the interview data. The investigator makes note of stories told during open-ended interviews and flags them for potential use in the final report. Data is entered into the database.
The researcher mails written surveys to all Board members with a requested return date and a stamped return envelope. Once the surveys are returned, the researcher codes and enters the data into the database so that it can be used independently as well as integrated when the case study progresses to the point of cross-case examination of data for all four cases.
Step 5. Evaluate and Analyze the Data
Within-case analysis is the first analysis technique used with each non-profit organization under study. The assigned investigator studies each organization�s written documentation and survey response data as a separate case to identify unique patterns within the data for that single organization. Individual investigators prepare detailed case study write-ups for each organization, categorizing interview questions and answers and examining the data for within-group similarities and differences.
Cross-case analysis follows. Investigators examine pairs of cases, categorizing the similarities and differences in each pair. Investigators then examine similar pairs for differences, and dissimilar pairs for similarities. As patterns begin to emerge, certain evidence may stand out as being in conflict with the patterns. In those cases, the investigator conducts follow-up focused interviews to confirm or correct the initial data in order to tie the evidence to the findings and to state relationships in answer to the research questions.
Step 6 Prepare the Report
The outline of the report includes thanking all of the participants, stating the problem, listing the research questions, describing the methods used to conduct the research and any potential flaws in the method used, explaining the data gathering and analysis techniques used, and concluding with the answers to the questions and suggestions for further research. Key features of the report include a retelling of specific stories related to the successes or disappointments experienced by the organizations that were conveyed during data collection, and answers or comments illuminating issues directly related to the research questions. The researcher develops each issue using quotations or other details from the data collected, and points out the triangulation of data where applicable. The report also includes confirming and conflicting findings from literature reviews. The report conclusion makes assertions and suggestions for further research activity, so that another researcher may apply these techniques to another electronic community network and its participants to determine whether similar findings are identifiable in other communities. Final report distribution includes all participants.
Applicability to Library and Information ScienceCase study research, with its applicability across many disciplines, is an appropriate methodology to use in library studies. In Library and Information Science, case study research has been used to study reasons why library school programs close (Paris, 1988), to examine reference service practices in university library settings (Lawson, 1971), and to examine how questions are negotiated between customers and librarians (Taylor, 1967). Much of the research is focused exclusively on the librarian as the object or the customer as the object. Researchers could use the case study method to further study the role of the librarian in implementing specific models of service. For example, case study research could examine how information-seeking behavior in public libraries compares with information-seeking behavior in places other than libraries, to conduct in-depth studies of non-library community based information services to compare with library based community information services, and to study community networks based in libraries.
ConclusionCase studies are complex because they generally involve multiple sources of data, may include multiple cases within a study, and produce large amounts of data for analysis. Researchers from many disciplines use the case study method to build upon theory, to produce new theory, to dispute or challenge theory, to explain a situation, to provide a basis to apply solutions to situations, to explore, or to describe an object or phenomenon. The advantages of the case study method are its applicability to real-life, contemporary, human situations and its public accessibility through written reports. Case study results relate directly to the common reader�s everyday experience and facilitate an understanding of complex real-life situations.
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Volume 18, No. 1, Art. 19 – January 2017
Case Study Research: Foundations and Methodological Orientations
Helena Harrison, Melanie Birks, Richard Franklin & Jane Mills
Abstract: Over the last forty years, case study research has undergone substantial methodological development. This evolution has resulted in a pragmatic, flexible research approach, capable of providing comprehensive in-depth understanding of a diverse range of issues across a number of disciplines. Change and progress have stemmed from parallel influences of historical transformations in approaches to research and individual researcher's preferences, perspectives, and interpretations of this design. Researchers who have contributed to the development of case study research come from diverse disciplines with different philosophical perspectives, resulting in a variety of definitions and approaches. For the researcher new to using case study, such variety can create a confusing platform for its application. In this article, we explore the evolution of case study research, discuss methodological variations, and summarize key elements with the aim of providing guidance on the available options for researchers wanting to use case study in their work.
Key words: case study; method; methodology; nursing research; qualitative; research design; research
Table of Contents
2. History and Evolution
3. Foundational Concepts
3.1 Definitions and descriptions
3.2 Methodology or method
3.3 Philosophical orientation
3.4 Philosophical variation
3.4.1 YIN: Realist—postpositivist
3.4.2 MERRIAM: Pragmatic constructivist
3.4.3 STAKE: Relativist—constructivist/interpretivist
4. Common Characteristics of Case Study Research
Case study research has grown in reputation as an effective methodology to investigate and understand complex issues in real world settings. Case study designs have been used across a number of disciplines, particularly the social sciences, education, business, law, and health, to address a wide range of research questions. Consequently, over the last 40 years, through the application of a variety of methodological approaches, case study research has undergone substantial development. Change and progress have stemmed from parallel influences from historical approaches to research and individual researcher's preferences, perspectives on, and interpretations of case study research. Central to these variations is the underpinning ontological and epistemological orientations of those involved in the evolution of case study research. Researchers who have contributed to the development of case study research come from diverse disciplines and their philosophical underpinnings have created variety and diversity in approaches used. Consequently, various designs have been proposed for preparing, planning, and conducting case study research with advice on key considerations for achieving success. As a result, while case study research has evolved to be a pragmatic, flexible research approach, the variation in definition, application, validity, and purposefulness can create a confusing platform for its use. 
In this article, we examine each of these issues in turn, with the aim of improving our understanding of case study research and clarifying the requisite tenets to consider when designing a case study. We begin with an overview of the history and evolution of case study research, followed by a discussion of the methodological and philosophical variations found within case study designs. We end with a summary of the common characteristics of case study research and a table that brings together the fundamental elements that we found common in all case study approaches to research. 
2. History and Evolution
Case study research as a strategy for methodological exploration, according to FLYVBJERG (2011) "has been around as long as recorded history" (p.302). Contemporary case study research is said to have its origins in qualitative approaches to research in the disciplines of anthropology, history, psychology, and sociology (MERRIAM, 1998; SIMONS, 2009; STEWART, 2014). Historical examples of case study stem as far back as the early nineteenth century with the biography of Charles DARWIN (STEWART, 2014). Most attribute the origins of case study research to studies undertaken in anthropology and social sciences in the early twentieth century when lengthy, detailed ethnographic studies of individuals and cultures were conducted using this design (JOHANSSON, 2003, MERRIAM, 2009; SIMONS, 2009; STEWART, 2014). Sociologists and anthropologists investigated people's lives, experiences, and how they understood the social and cultural context of their world, with the aim of gaining insight into how individuals interpreted and attributed meaning to their experiences and constructed their worlds (JOHANSSON, 2003; SIMONS, 2009). Such investigations were conducted in the natural setting of those experiences with results presented descriptively or as a narrative (MERRIAM, 2009). The most notable case studies include THOMAS and ZNANIECKI's (1958 [1918-1920]) study of Polish peasants in Europe and America and, the ethnographic work by MALINOWSKI (1913) in the Trobriand Islands in Melanesia that spanned over several years (CRESWELL, HANSON, PLANO CLARK & MORALES, 2007; JOHANSSON, 2003; STEWART, 2014). 
With the emergence and dominance of positivism in science in the late 1940s and 1950s, quantitative methods became a popular focus for the social sciences. As a result, surveys, experiments, and statistical methods anchored in quantitative approaches were favored and considered more rigorous than qualitative designs (JOHANSSON, 2003). The dominance of research using experimental designs continued through the 1960s and 1970s with quantitative empirical results considered to be gold standard evidence. Case studies continued to be used during this time, however usually as a method within quantitative studies or referred to as descriptive research to study a specific phenomenon (MERRIAM, 2009). At the same time, case study research was often criticized for its inability to support generalizability and thus considered to provide limited validity and value as a research design (JOHANSSON, 2003; MERRIAM, 2009; STEWART, 2014). This context led to a philosophical division in research approaches: those supporting positivism and quantitative approaches and those aligned with qualitative methods embedded in constructivist and interpretivist paradigms. 
Antecedents of modern day case study research are most often cited as being conducted in the Chicago School of Sociology between the 1920-1950s (STEWART, 2014). Here, anthropologists practiced their methods on university cultures or by conducting lengthy case studies involving field-based observations of groups with the aim of understanding their social and cultural lives (CRESWELL et al., 2007; JOHANSSON, 2003; STEWART, 2014). Parallel to the use of case studies in anthropology, medicine and disciplines in the social sciences such as sociology, education and political science also embraced case study as a form of inquiry (ANTHONY & JACK, 2009; BROWN, 2008; CRESWELL et al., 2007; GEORGE & BENNETT, 2005; GERRING, 2004; SIMONS, 2009; YIN, 2014). 
A second generation of case study researchers emerged with the advent of grounded theory methodology (GLASER & STRAUSS, 1967). Grounded theory "merged qualitative field study methods from the Chicago School of Sociology with quantitative methods of data analysis" (JOHANSSON, 2003, p.8), resulting in an inductive methodology that used detailed systematic procedures to analyze data. This renewed interest in qualitative methodology led to a revival in the use of case study in a number of disciplines (ANTHONY & JACK, 2009; GEORGE & BENNETT, 2005; JOHANSSON, 2003; MERRIAM, 2009; STAKE, 1995). According to JOHANSSON (2003), Robert YIN followed this progress, and drawing on scientific approaches to research gained from his background in the social sciences, applied experimental logic to naturalistic inquiry, and blended this with qualitative methods, further bridging the methodological gap and strengthening the methodological quality of case study research. He presented a structured process for undertaking case study research where formal propositions or theories guide the research process and are tested as part of the outcome, highlighting his realist approach to qualitative case study research. While still qualitative and inductive, it was deterministic in nature with an emphasis on cause and effect, testing theories, and an apprehension of the truth (BROWN, 2008; YIN, 2014). 
Similarly, the uptake of case study research in the political sciences, particularly during the 1980's and 1990’s, led to a more integrated methodological approach with the aim of theoretical development and testing (GEORGE & BENNETT, 2005). The integration of formal, statistical, and narrative methods in a single study, combined with the use of empirical methods for case selection and causal inference, demonstrated the versatility of case study design and made a significant contribution to its methodological evolution (ibid.). Similarly, case studies in international relations integrated rigorous, standardized methods with statistical and formal methods, including qualitative comparative analysis and process tracing to improve understanding of world politics (BENNETT & ELMAN, 2007; GERRING, 2004; LEVY, 2007). According to GEORGE and BENNETT (2005) "scholars have formalized case study methods more completely and linked them to underlying arguments in the philosophy of science" (p.6). The continued use of case study to understand the complexities of institutions, practices, processes, and relations in politics, has demonstrated the utility of case study for researching complex issues, and testing causal mechanisms that can be applied across varied disciplines. 
Corresponding with these developments, in the 1970's, educational research embraced case study as a way to evaluate curriculum design and innovation (MERRIAM, 2009; SIMONS, 2009; STAKE, 1995). Methods were required that could be used to explore factors such as participants' perspectives and the influence of socio-political contexts on curriculum successes and failures (SIMONS, 2009). Development of case study research in education, focused on the need to determine the impact of educational programs and provide relevant evidence for policy and practice decisions that supported social and educational change in the United Kingdom and the United States (ibid.). The most significant contributors to this field were STAKE (1995, 2006) and MERRIAM (1998, 2009). STAKE (1995), an educational psychologist with an interest in developing program evaluation methods, used a constructivist orientation to case study. This resulted in placing more emphasis on inductive exploration, discovery, and holistic analysis that was presented in thick descriptions of the case. Similarly, MERRIAM (1998, 2009) used case study research to explore and evaluate educational programs. MERRIAM's approach emphasized defining and understanding the case through the products of inquiry and drew on the work of both YIN and STAKE. MERRIAM (2009) described case study research by its characteristics: particularistic, descriptive and heuristic, highlighting the purpose and qualitative nature of case study research, the focus on a specific entity and, the motivation to understand and describe the findings. Similar to STAKE (1995, 2006), MERRIAM (1998, 2009) was not as structured in her approach as YIN (2014), but promoted the use of a theoretical framework or research questions to guide the case study and organized, systematic data collection to manage the process of inquiry. 
Simple in theory yet complex in nature, the planning, preparation and execution of case study research has developed to a point where the continued application of case study research across a number of professions particularly education, health, and social sciences, has provided a unique platform for credible research endeavors. Case study research has grown in sophistication and is viewed as a valid form of inquiry to explore a broad scope of complex issues, particularly when human behavior and social interactions are central to understanding topics of interest (ANTHONY & JACK, 2009; FLYVBJERG, 2011; GEORGE & BENNETT, 2005; LUCK, JACKSON & USHER, 2006; MERRIAM, 2009; STAKE, 2006; YIN, 2014). 
In Figure 1, developed by JOHANSSON (2003) and adapted for this discussion, a summary of the evolution of case study across a timeline dating back to 1600 is displayed. Key contributors to case study research and major contextual influences on its evolution are included. As the figure highlights, early case studies were conducted in the social sciences. With the dominance of logical positivism from the 1940's through to the 1960's and 1970's case study methodology was viewed with skepticism and criticism. The development of grounded theory in the 1960's led to a resurgence in case study research, with its application in the social sciences, education, and the humanities. Over the last 50 years, case study has been re-established as a credible, valid research design that facilitates the exploration of complex issues.
Figure 1: The history and evolution of case study research (JOHANSSON, 2003, p.7) 
3. Foundational Concepts
While over time the contributions of researchers from varied disciplines have helped to develop and strengthen case study research, the variety of disciplinary backgrounds has also added complexity, particularly around how case study research is defined, described, and applied in practice. In the sections that follow, the nature of this complexity in explored. 
3.1 Definitions and descriptions
There are a number of definitions and descriptions presented across the literature, which can create confusion when attempting to understand case study research. The most common definitions come from the work of YIN (2014), STAKE (1995), and MERRIAM (2009). YIN's two-part definition (2014) focuses on the scope, process, and methodological characteristics of case study research, emphasizing the nature of inquiry as being empirical, and the importance of context to the case. On the other hand, STAKE (1995) takes a more flexible stance and while concerned with rigor in the processes, maintains a focus on what is studied (the case) rather than how it is studied (the method). For STAKE case study research is "the study of the particularity and complexity of a single case, coming to understand its activity within important circumstances" (p.xi). MERRIAM (2009) includes what is studied and the products of the research when defining case study as: "... an in depth description and analysis of a bounded system" (p.40). Like STAKE, MERRIAM emphasizes the defining feature of case study research as being the object of the study (the bounded system; i.e., the case) adding that case study research focuses on a particular thing and that the product of an investigation should be descriptive and heuristic in nature. In discussing the proliferation of definitions (and subsequent confusion), FLYVBJERG (2011) contends that using a simple definition might be a more useful approach, citing the MERRIAM-WEBSTER DICTIONARY's (2009) definition, as an example that captures the key requisites in the context of research: "an intensive analysis of an individual unit (as a person or community) stressing developmental factors in relation to environment" (p.103). These varied definitions stem from the researchers' differing approaches to developing case study methodology and often reflect the elements they emphasize as central to their designs. The diversity of approaches subsequently adds diversity to definition and description. 
3.2 Methodology or method
A further challenge to understanding case study research relates to it being referred to and used as both a methodology and a method. MILLS (2014) distinguishes methods as procedures and techniques employed in the study, while methodology is the lens through which the researcher views and makes decisions about the study. Given the variation in definitions and descriptions, referring to case study research as a methodology and/or a single method can be perplexing, misleading, and at times counterproductive (ANTHONY & JACK, 2009; BOBLIN, IRELAND, KIRKPATRICK & ROBERTSON, 2013; FLYVBJERG, 2011). Furthermore, advocates of case study encourage the use of both quantitative and qualitative methods within their designs adding further obscurity to the question of methodology (MERRIAM, 1998; STAKE, 1995; STEWART, 2014; YIN, 2014). 
The ambiguity about case study being either or both a methodology and method, is compounded by the terminology used in discussions about case study. Across the literature, case study is referred to as a methodology and a method, an approach, research and research design, research strategy, and/or a form of inquiry (ANTHONY & JACK, 2009; BROWN, 2008; CRESWELL, 2014; GERRING, 2004; MERRIAM, 2009; SIMONS, 2009, STAKE, 1995, 2006; STEWART, 2014; YIN, 2014). Often these terms are used interchangeably without definitional clarity. For example, YIN (2014) discusses case study research and in the context of presenting case study, refers to it as a research method while emphasizing the procedures used. He does not use the terms methodology or strategy. CRESWELL (2014) refers to case studies as a qualitative design, while others use the term case study (FLYVBJERG, 2011; STAKE, 1995, 2006; STEWART, 2014), qualitative case study (MERRIAM, 2009), or describe case study as an approach (SIMONS, 2009). This mixed use of terminology is confusing given the definitional separations between methodology and methods and the varied application of case study in research endeavors. 
Prominent case study researchers do however emphasize that an overarching methodology shapes a case study design and that multiple sources of data and methods can be used (MERRIAM, 2009; STAKE, 2006; YIN, 2014), thus providing the distinction between the two. This distinction accentuates the need for researchers to describe the particular underpinning methodology adopted and to clarify the alignment of chosen methods used with their philosophical assumptions and their chosen approach. Exploring the philosophical orientation of case study research and variations in different case study approaches can help to clarify these differences, and promote a better understanding of how to apply these principles in practice. 
3.3 Philosophical orientation
Many methodologies are aligned with specific philosophical positions that guide the research process. Case study, however, has a practical versatility in its agnostic approach whereby "it is not assigned to a fixed ontological, epistemological or methodological position" (ROSENBERG & YATES, 2007, p.447). Philosophically, case study research can be orientated from a realist or positivist perspective where the researcher holds the view that there is one single reality, which is independent of the individual and can be apprehended, studied and measured, through to a relativist or interpretivist perspective. A relativist or interpretivist perspective adopts the premises that multiple realities and meanings exist, which depend on and are co-created by the researcher (LINCOLN, LYNHAM & GUBA, 2011; YIN, 2014). This philosophical versatility provides the researcher with the opportunity to decide the methodological orientation used in the conduct of the case study (STEWART, 2014; YIN, 2014). Examples of this choice are discussed later where the philosophical variations of MERRIAM (2009), STAKE (1995), and YIN (2014) are explicated. 
In the context of healthcare research and specifically nursing, LUCK et al. (2006) describe case study research as "a bridge across paradigms" (p.103). As a result, some case study approaches are either quantitatively or qualitatively orientated while others encompass both qualitative and quantitative aims and methods (MERRIAM, 2009; MILES, HUBERMAN & SALDANA, 2014; YIN, 2014). DENZIN and LINCOLN (2011) emphasize the qualitative essence of case study, while acknowledging its evolution and fluidity with regard to accommodating varied ontologies, epistemologies, methodologies, and methods. This ability to accommodate a range of philosophical positions is seen as an advantage whereby case study enables the opportunity to design research that can be specifically tailored to the inherent complexity of the research problem (ANTHONY & JACK, 2009; CASEY & HOUGHTON, 2010; FLYVBJERG, 2011; FARQUHAR, 2012; LUCK et al., 2006; MERRIAM, 2009; STAKE, 2006; YIN, 2014). 
Case study research is most often described as qualitative inquiry (CRESWELL, 2014; DENZIN & LINCOLN, 2011; MERRIAM, 2009; MILES et al., 2014; STAKE, 2006). Qualitative paradigms are broad and can encompass exploratory, explanatory, interpretive, or descriptive aims. Examples include narrative research, phenomenology, grounded theory, and ethnography (DENZIN & LINCOLN, 2011). Each methodology is unique in approach depending on the ontological and epistemological stance, however all stem from the motivation to explore, seek understanding, and establish the meaning of experiences from the perspective of those involved (ibid.; see also MERRIAM, 2009). For this purpose, qualitative researchers can employ a broad scope of methods and interpretative practices in any one study, although they typically include observations, interviews, and analysis of participants' words (DENZIN & LINCOLN, 2011; MERRIAM, 2009). DENZIN and LINCOLN (2011, pp. 8-10) summarize the characteristics of qualitative research into five key attributes:
reducing the use of positivist or post positivist perspectives;
accepting postmodern sensibilities;
capturing the individual's point of view;
examining the constraints of everyday life;
securing rich descriptions. 
These attributes are commonly exemplified in case study research. The fundamental goal of case study research is to conduct an in-depth analysis of an issue, within its context with a view to understand the issue from the perspective of participants (MERRIAM, 2009; SIMONS, 2009; STAKE, 2006, YIN, 2014). Like other forms of qualitative research, the researcher will seek to explore, understand and present the participants' perspectives and get close to them in their natural setting (CRESWELL, 2013). Interaction between participants and the researcher is required to generate data, which is an indication of the researcher's level of connection to and being immersed in the field. Because of this, constructivism and interpretivism commonly permeate the implementation of this research design. Methods used in case study to facilitate achieving the aim of co-constructing data most often include observations, interviews, focus groups, document and artifact analysis (MERRIAM, 2009; SIMONS, 2009; STAKE, 1995; 2006; STEWART, 2014; YIN, 2014). The researcher's perceptions and interpretations become part of the research and as a result, a subjective and interpretive orientation flows throughout the inquiry (CRESWELL, 2014). Subjectivity is openly acknowledged and to manage this, the researcher embraces a reflexive stance within the study, adopting methods such as memoing and journaling that support this position (DENZIN & LINCOLN, 2011; MILES et al., 2014, STAKE, 2006; YIN, 2014). 
3.4 Philosophical variation
In choosing a methodological position, careful consideration of the different case study approaches is required to determine the design that best addresses the aim of the study, and that aligns with the researcher's worldview. The goal of this alignment is to engender coherence between the researcher's philosophical position, their research question, design, and methods to be used in the study (FARQUHAR, 2012; LUCK et al., 2006; STEWART, 2014; YIN, 2014). To assist in understanding and achieving this alignment, the qualitative case study approaches developed by YIN (2014), STAKE (1995) and MERRIAM (1998, 2009) are explored in the following sections. Examples are provided of how these researchers' philosophical orientation influences the application of case study in practice. 
3.4.1 YIN: Realist—postpositivist
YIN (2014) conceptualizes case study research as a form of social science. Post-positivism is evident in how he defines "case study as a form of empirical inquiry" (p.16). YIN himself describes his approach to case study as using a "realist perspective" (p.17) and focuses on maintaining objectivity in the methodological processes within the design. 
Postpositivist qualitative researchers conduct research that embraces the ideals of objectivity and the generalizability of results (ELLINGSON, 2011). The goal of a postpositivist researcher is to use science as a way to apprehend the nature of reality while understanding that all measurement is imperfect. Therefore, emphasis is placed on using multiple methods with triangulation to circumvent errors and understand what is happening in reality as close as possible to the "truth" (LINCOLN et al., 2011). The researcher will often categorize qualitative data to create quantitative data that can then be analyzed using statistical methods. Validity of research results are verified through the scrutiny of others and, as such, adherence to mechanisms that ensure rigor in data collection and analysis is vital. Furthermore, postpositivists accept that everyone is inherently biased in worldviews, which ultimately influence how the methods used are deployed. Interaction with research subjects therefore needs to be minimized and subjectivity managed to avoid biasing the results (ibid.). 
Embedded within YIN's (2014) case study design are the hallmarks of a postpositivist approach to research: seeking rival explanations and falsifying hypotheses, the capability for replication with a multiple case study design, the pursuit of generalizations (if required), minimizing levels of subjectivity, and the use of multiple methods of qualitative and quantitative data collection and analysis. While objectivity is a goal, YIN also recognizes the descriptive and interpretive elements of case study. According to YIN what makes case study research distinct from experimental studies is the case study is investigated in context, examined in its "real world setting" (p.16). Selection of cases is based on the purpose of the research and related to the theoretical propositions about the topic of interest. YIN suggests careful screening in the selection of cases to ensure specific relevance to the issues of interest and the use of replication logic: cases are chosen to produce anticipated contrasting findings (theoretical replication) or similar findings (literal replication). Precision, process, and practicality are core attributes of YIN's approach to case study. Design features are sequentially structured and motivated by empirical application. This positioning reflects the axiology of postpositivism where maintaining intellectual honesty, managing bias, and acknowledging limitations, coupled with meticulous data collection and accurate reporting are critical elements in the conduct of research (KILLAM, 2013; YIN, 2014). 
3.4.2 MERRIAM: Pragmatic constructivist
MERRIAM (1998) maintains a constructivist approach to case study research, whereby the researcher assumes that reality is constructed intersubjectively through meanings and understandings developed socially and experientially. Like YIN (2014), MERRIAM (1998, 2009) asserts that when information is plentiful and concepts abstract, it is important to utilize processes that help interpret, sort, and manage information and that adapt findings to convey clarity and applicability to the results. In this way, MERRIAM's perspective brings forth a pragmatic approach to constructivist inquiry. MERRIAM (2009) acknowledges case study research can use both quantitative and qualitative methods; however, when working on qualitative case studies, methods aimed at generating inductive reasoning and interpretation rather than testing hypothesis take priority. Cases are selected based on the research purpose and question, and for what they could reveal about the phenomenon or topic of interest. The aim is to provide a rich holistic description that illuminates one's understanding of the phenomena (MERRIAM, 1998). Interviews are the most common form of qualitative data collection, although MERRIAM does not stipulate prioritizing a particular method for data collection or analysis, she does emphasize the importance of rigorous procedures to frame the research process. Advocating for careful planning, development, and execution of case study research, MERRIAM (1998, 2009) discusses the pragmatic structures that ensure case study research is manageable, rigorous, credible, and applicable. Processes such as descriptive, thematic and content analysis, and triangulation are significant in ensuring the quality of a study, therefore, methods of data collection and analysis need to be organized and systematized with a detailed chain of evidence (MERRIAM, 2009). Theoretical frameworks or research questions are used and drawn from the literature or discipline (MERRIAM, 1998). According to BROWN (2008), Merriam's style brings forth a practical application of pluralistic strategies that guide pragmatic constructivist research to derive knowledge about an area of inquiry. 
3.4.3 STAKE: Relativist—constructivist/interpretivist
STAKE (1995, 2006) has an approach to case study research that is qualitative and closely aligned with a constructivist and interpretivist orientation. While having a disciplined approach to the process and acknowledging that case study can use quantitative methods, STAKE's approach is underpinned by a strong motivation for discovering meaning and understanding of experiences in context. The role of the researcher in producing this knowledge is critical, and STAKE emphasizes the researcher's interpretive role as essential in the process. An interpretative position views reality as multiple and subjective, based on meanings and understanding. Knowledge generated from the research process is relative to the time and context of the study and the researcher is interactive and participates in the study. In terms of epistemology, STAKE argues that situation shapes activity, experience, and one's interpretation of the case. For STAKE (2006), to understand the case "requires experiencing the activity of the case as it occurs in its context and in its particular situation" (p.2). The researcher attempts to capture her or his interpreted reality of the case, while studying the case situationally enables an examination of the integrated system in which the case unfolds. Similar to YIN (2014) and MERRIAM (2009), a case or cases are selected for what they can reveal about topic of interest and depend on the aim and conditions of the study. A case is selected because it is interesting in itself or can facilitate the understanding of something else; it is instrumental in providing insight on an issue (STAKE, 2006). 
For STAKE, multiple sources and methods of data collection and analysis can be used, however, interviews and observations are the preferred and dominant data collection method. In seeking understanding and meaning, the researcher is positioned with participants as a partner in the discovery and generation of knowledge, where both direct interpretations, and categorical or thematic grouping of findings are used. STAKE (1995) recommends vignettes—episodes of storytelling—to illustrate aspects of the case and thick descriptions to convey findings, a further illustration of his constructivist and interpretivist approach to case study research. 
BROWN (2007) suggests the three approaches used by these seminal researchers rest along a quantitative-qualitative continuum where the postpositivist methodology of YIN (2014) sits at one end, STAKE's interpretivist design (1995, 2006) sits at the other end and MERRIAM (1998, 2009) who as a pragmatic constructivist draws on the elements of both, rests toward the center. BROWN (2008) sums up the influences of each, saying that "case study research is supported by the pragmatic approach of Merriam, informed by the rigour of Yin and enriched by the creative interpretation described by Stake" (p.9). While some may argue that mixing qualitative and quantitative methods could threaten the veracity of the research (BOBLIN et al., 2013; SANDELOWSKI, 2011), MERRIAM's approach demonstrates that when the integrity of the design is robust, methodological flexibility can be accommodated. 
4. Common Characteristics of Case Study Research
Despite variation in the approaches of the different exponents of case study, there are characteristics common to all of them. Case study research is consistently described as a versatile form of qualitative inquiry most suitable for a comprehensive, holistic, and in-depth investigation of a complex issue (phenomena, event, situation, organization, program individual or group) in context, where the boundary between the context and issue is unclear and contains many variables (CRESWELL, 2014; FLYVBJERG, 2011; MERRIAM, 2009; SIMONS, 2009; STAKE, 2006; YIN, 2014). Case study research can be used to study a range of topics and purposes (SIMONS, 2009; STAKE, 2006; STEWART, 2014) however, the essential requisite for employing case study stems from one's motivation to illuminate understanding of complex phenomena (MERRIAM, 2009; STAKE, 2006; YIN, 2014). Primarily exploratory and explanatory in nature, case study is used to gain an understanding of the issue in real life settings and recommended to answer how andwhy or less frequently what research questions (FLYVBJERG, 2011; MERRIAM, 2009; SIMONS, 2009; STAKE, 2006; STEWART, 2014; YIN 2014). 
Defining the case (unit of analysis or object of the study) and bounding the case can be difficult as many points of interest and variables intersect and overlap in case study research. Developing research questions and/or propositions to select the case, identify the focus, and refine the boundaries is recommended to effectively establish these elements in the research design (MERRIAM, 2009; STAKE, 2006; YIN, 2014). Bounding the case is essential to focusing, framing, and managing data collection and analysis. This involves being selective and specific in identifying the parameters of the case including the participant/s, location and/or process to be explored, and establishing the timeframe for investigating the case (MERRIAM, 2009; STAKE, 2006; YIN, 2014). 
The use of multiple methods to collect and analyze data are encouraged and found to be mutually informative in case study research where together they provide a more synergistic and comprehensive view of the issue being studied (FLYVBJERG, 2011; MERRIAM, 2009; STAKE, 2006; YIN, 2014). How the methods are used will vary and depend on the research purpose and design, which is often a variation of a single or multiple case study research design. Interviews and focus groups, observations, and exploring artifacts are most commonly employed to collect and generate data with triangulation of methods and data, however, this is not exclusive. 
The fundamental elements of case study research (Table 1) are evident in the approaches of MERRIAM (2009), STAKE (1995, 2006), and YIN (2014) as well as other case study researchers who have contributed to the development and discussion of case study research (CRESWELL, 2013, 2014; FLYVBJERG, 2011; GEORGE & BENNETT, 2007; MILES et al., 2014; SIMONS, 2009). These elements delineate case study from other forms of research and inform the critical aspects of the research design and execution.
Object of the case study identified as the entity of interest or unit of analysis
Program, individual, group, social situation, organization, event, phenomena, or process
A bounded system
Bounded by time, space, and activity
Encompasses a system of connections
Bounding applies frames to manage contextual variables
Boundaries between the case and context can be blurred
Studied in context
Studied in its real life setting or natural environment
Context is significant to understanding the case
Contextual variables include political, economic, social, cultural, historical, and/or organizational factors
Chosen for intensive analysis of an issue
Fieldwork is intrinsic to the process of the inquiry
Subjectivity a consistent thread—varies in depth and engagement depending on the philosophical orientation of the research, purpose, and methods
Reflexive techniques pivotal to credibility and research process
Selecting the case
Based on the purpose and conditions of the study
Involves decisions about people, settings, events, phenomena, social processes
Scope: single, within case and multiple case sampling
Broad: capture ordinary, unique, varied and/or accessible aspects
Methods: specified criteria, methodical and purposive; replication logic: theoretical or literal replication (YIN, 2014)
Multiple sources of evidence
Multiple sources of evidence for comprehensive depth and breadth of inquiry
Methods of data collection: interviews, observations, focus groups, artifact and document review, questionnaires and/or surveys
Methods of analysis: vary and depend on data collection methods and cases; need to be systematic and rigorous
Triangulation highly valued and commonly employed
Case study design
Descriptive, exploratory, explanatory, illustrative, evaluative
Single or multiple cases
Embedded or holistic (YIN, 2014)
Particularistic, heuristic, descriptive (MERRIAM, 1998, 2009)
Intrinsic, instrumental, and collective (STAKE, 1995, 2006)
Table 1: Case study elements and descriptors 
A final, critical point when conducting case study research is the importance of careful preparation and planning, coupled with the development of a systematic implementation structure (FLYVBJERG, 2011; MERRIAM, 2009; STAKE, 2006; STEWART, 2014; YIN, 2014). As discussed earlier, ensuring the alignment of philosophy and methodology with the research purpose and methods employed underpins a rigorous research process (STEWART, 2014). Clarity in this alignment is fundamental to ensuring the veracity of the research and depends on the design developed. During this process, researchers are encouraged to "logically justify their philosophical position, research design and include a coherent argument for inclusion of varying research methods" (LUCK et al., 2006, p.107). Study propositions, theory, research or issue questions work as a conceptual framework and need to align with the case to guide the design and determine methods of data collection and analysis (STAKE, 2006; STEWART, 2014; YIN, 2014). Maintaining meticulous records and a systematic chain of evidence over the duration of the study is critical; as is being able to access, present and explain procedures supports the ethical integrity and rigor of the research and findings (MERRIAM, 2009; STEWART, 2014; YIN, 2014). Collective alignment of these elements articulates a justifiable framework for the research study and cultivates trustworthiness and the validity, reliability and credibility of the research findings. 
Considering these fundamental elements and common approaches to case study research, the definition from CRESWELL et al. (2007) seems to best capture the full depth and breadth of case study concepts and descriptions. The authors describe case study as "a methodology, a type of design in qualitative research, an object of study and a product of the inquiry" (p.245). They conclude with a definition that collates the hallmarks of key approaches and represents the core features of a case study:
"Case study research is a qualitative approach in which the investigator explores a bounded system (a case) or multiple bounded systems (cases) over time through detailed, in-depth data collection involving multiple sources of information (e.g., observations, interviews, audiovisual material, and documents and reports) and reports a case description and case-based themes" (ibid.). 
Since the 1980's a broad scope of case study approaches have developed. This range accentuates the flexibility of case study research as a distinct form of inquiry that enables comprehensive and in-depth insight into a diverse range of issues across a number of disciplines. While differences exist in some areas, commonalities are evident that can guide the application of a case study research design. Key contributors to the development of case study agree that the focus of a case study is the detailed inquiry of a unit of analysis as a bounded system (the case), over time, within its context. The versatility of case study research to accommodate the researcher's philosophical position presents a unique platform for a range of studies that can generate greater insights into areas of inquiry. With the capacity to tailor approaches, case study designs can address a wide range of questions that ask why, what, and how of an issue and assist researchers to explore, explain, describe, evaluate, and theorize about complex issues in context. Outcomes can lead to an in-depth understanding of behaviors, processes, practices, and relationships in context. Professions including the social sciences, education, health, law, management, business, and urban planning have embraced case study research, demonstrating these outcomes. Ongoing application of and sound debate about the value, validity, and capability of case study research have strengthened the efficacy of case study approaches as powerful forms of qualitative research. 
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Helena HARRISON, MN(Ed) is a PhD candidate in the College of Healthcare Sciences, Division of Tropical Health and Medicine, James Cook University, Australia. Her research interests include undergraduate and postgraduate nurse education with her current study focusing on the practice readiness of new graduate registered nurses in Australia.
Nursing, Midwifery & Nutrition
College of Healthcare Sciences
Division of Tropical Health and Medicine
James Cook University
Angus Smith Drive, Douglas, QLD, Australia 4811
Melanie Birks, PhD is professor and Head of Nursing, Midwifery and Nutrition at James Cook University, Australia. Her research interests are in the areas of accessibility, innovation, relevance and quality in nursing education.
Nursing, Midwifery & Nutrition
College of Healthcare Sciences
Division of Tropical Health and Medicine
James Cook University
Angus Smith Drive, Douglas, QLD, Australia 4811
Tel: +61-7- 4781- 4544
Richard Franklin, Ph.D. is an associate professor at the College of Public Health, Medical & Veterinary Sciences at James Cook University. Richard's public health projects have explored injury prevention and safety promotion and focused areas of farm safety, rural safety, occupational health and safety, falls, disasters, health promotion, and alcohol and aquatic safety. Richard's research interests include translating evidence into practice, epidemiological, program and product evaluation, surveillance and using mixed methods research for solving real world problems.
Public Health & Tropical Medicine
Building 41, Room 213
College of Public Health, Medical & Veterinary Sciences
Division of Tropical Health and Medicine
James Cook University
Angus Smith Drive, Douglas, QLD, Australia 4811
Tel: +61-7- 4781 5939
Jane Mills, PhD is professor and Pro Vice Chancellor of the College of Health at Massey University in New Zealand. Her research interests are primary health care, public health and health systems strengthening.
College of Health
Private Bag 102904
North Shore Auckland, New Zealand, 0745
Tel.: +64 9 414 0800 extn 49087
Harrison, Helena; Birks, Melanie; Franklin, Richard & Mills, Jane (2017). Case Study Research: Foundations and Methodological Orientations [34 paragraphs]. Forum Qualitative Sozialforschung / Forum: Qualitative Social Research, 18(1), Art. 19,