Without formal avenues for claims-making or political participation, refugees must find their own means of securing services from state and non-state providers. This article asks why some refugee communities are more effective than others in mitigating community problems. I present a framework for understanding how refugees' social networks shape the constraints and capabilities for collective action. I analyze a field experiment where I organized community meetings with Syrian refugees in Lebanon and Jordan, randomly assigning the recruitment method for meetings to introduce exogenous variation in network structure. During meetings, participants were tasked with resolving collective action problems. I examine the dynamics of subsequent group discussion. Results show that although densely networked refugee groups exhibit more cooperation, they suffer from a resource diversity disadvantage. Group diversity facilitates access to resources that may help refugee communities confront community problems. The novel experimental design allows for separately identifying group-level and individual-level mechanisms.