To organize and implement social development projects through interorganizational collaboration is common, but lack empirical studies from a psychological perspective. The study´s aim was to make a collaboration analysis on the implementing actors within a social development project, to understand how the collaboration was functioning. The study took place within a project for marginalized groups in Tanzania, arranged by a Swedish NGO and implemented by interorganizational collaboration. Eight participants were interviewed on six areas: Environment, Membership characteristics, Process and Structure, Communication, Purpose, and Resources. The findings highlight the complexity of interorganizational collaboration. The studied collaborative network is overall working in the same direction, but has both functional and dysfunctional areas where the dysfunctional need to be improved for the collaboration to work well. The study indicates that interorganizational collaboration brings benefits for social development projects, and the six areas studied seem to cover essential areas of interorganizational collaboration.