The social networks of 27 severely mentally ill (SMI) clients of two community mental health centers were compared with those of 19 clients who had less severe disorders. The networks of the SMI clients were smaller and less reciprocal and contained fewer family members. SMI clients' networks were also more likely to include social service providers, such as group home staff and caseworkers. These social service providers gave direct advice and medical, food, and financial assistance in addition to emotional support, but the relationships were nonreciprocal. Clients with the fewest indigenous supports had the most social service links. These findings suggest that mental health services for SMI persons may provide substitute social supports that serve a broader function than more traditional emotional therapy.