In this study we test whether differences between patient and provider explanatory models of diabetes affect self-management and glucose control in type 2 diabetes patients. Diabetic patients (n=60) and family practice physicians (n=39) in Guadalajara, Mexico, responded to a structured explanatory model interview (130 questions on causes, symptoms, and treatments). A cultural consensus analysis indicated a widely shared model among physicians and provided a single shared set of answers to the questions. Patient-provider congruence in beliefs was assessed by comparing each patient’s responses with the physician answer set. Congruence in beliefs predicted self-management behaviors (r=0.27, p=.03), more than educational level (r=0.16, p=.23), but was not predictive of A1C (r=0.12, p=.40). Differences between patient and physician explanatory models can adversely affect patient-directed activities and may indirectly affect glycemic control by affecting self-management. These differences may be due to low patient educational level and resulting problems in understanding biomedical approaches to diabetes.