Religious ritual has long been seen as a pivotal mechanism for promoting and maintaining cohesion within a community, but the processes by which this occurs remain poorly understood. Some theorize that ritual promotes sociality by requiring costly investments of time, effort or resources as reliable signals of commitment to the group. Public displays of devotion allow individuals to monitor each other's behavior and thus serve to prevent cheating and encourage cooperation. These issues will be studied by a dissertation project in cultural anthropology focusing on the Afro-Brazilian religion of Candomble. The ceremonies and feasts of the religion can be particularly extravagant and expensive for followers, yet it is a growing spiritual option for many poor and low middle-class Brazilians. This research will investigate the relationship between religious commitment and solidarity in Candomble congregations in the city of Salvador da Bahia. It will test the hypothesis that members of these religious communities who display higher commitment levels to the religion will also be more cooperative and cohesive. Commitment will be assessed through a combination of qualitative and quantitative methods including participant observation, semi-structured interviews and a commitment scale. Cooperation will be measured through the use of an experimental economic game. Social network analysis will reveal levels of cohesion and solidarity within each community. The broader impact of this project is gaining an understanding of the elements which characterize a successful religious group, which is increasingly important given the current resurgence of religion as a political and social motivation. Parallel processes may also operate in other social institutions that restrict membership. Additionally, this research project will advance the training of a doctoral student and provide training opportunities for two undergraduate assistants from Brazilian universities.