Generally known as the idiographic approach, it emphasizes the uniqueness of each individual. Using case studies on a specific person is how a scientist would study psychodynamic behavior (assumptions). Each perspective has its strengths and weaknesses. It's good to have to do a case study, so you can build a relationship and the client will be more open and willing to evaluate. A weakness of this would be that because the case studies are individual, it is not possible to generalize to others