In psychology, most of the case studies must be a single case. However, there are times when multiple cases are studied. When the latter is the cases, the principle of replication is hinged on when choosing the cases to include. The case study must at the end have some vivid and clear advantages and disadvantages, and it must give results that are valid and reliable so that future research can be developed from the study. When a case study psychology is done by a group instead of an individual; the group members are expected to get familiar with the information and go in search of additional materials for the task. They should meet as a group from time to time during which each member interprets the problem and offer a solution according to their private findings. With the nuanced viewpoints and solutions, the group will now have lots of approaches in solving the problem. This is very feasible because the case being investigated in every case study psychology does not have one correct solution, and the group leader or any particular member does not suggest the answer. It must be a situation where the group reaches a consensus before writing a research paper as the case study report.