I  have six references on case study in my library. Robert K. Yin wrote two seminal books on case studies, one in 1993 (now in a 2nd edition, 1993 was the 1st edition) and the other in 1989 (now in the 4th edition, 1989 was the 1st edition).  I have the 1994 edition (2nd edition of the 1989 book), and in it Yin says that “case studies are increasingly commonplace in evaluation research…are the preferred strategy when “how” and “why” questions are being posed, when the investigator has little control over events, and when the focus in on a contemporary phenomenon within some real-life context.

So what exactly is a case study?

A case study is typically an in-depth study of one or more individuals, institutions, communities, programs, populations. Whatever the “case” it is clearly bounded and what is studied is what is happening and important within those boundaries. Case studies use multiple sources of information to build the case.  For a more detailed review see Wikipedia

There are three types of case studies

• Explanatory
• Exploratory
• Descriptive

Over the years, case method has become more sophisticated.

Brinkerhoff has developed a method, the Success Case Method, as an evaluation approach that “easier, faster, and cheaper than competing approaches, and produces compelling evidence decision-makers can actually use.”  As an evaluation approach, this method is quick and inexpensive and most of all, produces useful results.

Robert E. Stake has taken case study beyond one to many with his recent book, Multiple Case Study Analysis.  It looks at cross-case analysis and can be used when broadly occurring phenomena need to be explored, such as leadership or management.

I’ve mentioned four of the six books, if you want to know the others, let me know.