Basically a case study is the longitudinal method of study. Psychology has a broad scope and in psychology research works are also frequently carried out. There are various methods of study in psychology which includes observations, clinical studies, survey methods, experimental methods and case studies. Therefore, case studies are used in psychology as a method of study. Case study is important in psychology because it gives the in-depth analysis of a particular topic. Suppose, you are studying the behavior of employees in different workplaces. Now if you take data from a company and compares the satisfaction of employees from the company in different years, then you will better analyze your topic. In this way when a case study is written on a psychological related topic it gives more details about a subject and issue. In this way case study becomes an important method of study in psychology.