This study involves a cooperation project between the Swedish health benefits system and a local psychiatric clinic. The study has a qualitative method and the data has been collected from the cooperation board and doctors at the clinic. The cooperation board consists of representatives from all parties. The projects aim is to develop a method for combating long-term sick leave in patients at the clinic. The aim of the study has been do discover what factors are relevant in order to have good cooperation and how cooperation can develop an organization. Our conclusion is that there are several factors that good cooperation are dependent upon. These are among others communication and the motivation of the participants.