To reduce modifiable diabetes risk factors' in overweight and obese AI men residing on the Colville reservation through a community-based, culturally informed intervention, the study specifically aims to: 1. conduct focus groups and interviews with adult members of Colville tribe to inform the adaptation, manualization and implementation of a culturally informed diabetes prevention program among overweight and obese AI men; 2. evaluate the effectiveness of a community-based, culturally informed diabetes prevention intervention by assessing between group changes in: Primary Outcomes: weight, dietary fat and caloric intake, vegetable consumption, and physical activity; Secondary Outcomes: physical fitness, blood pressure, lipids, self-reported quality of life; and, 3. evaluate the sustainability of the diabetes prevention intervention by assessing participant perceptions of program component fit through focus group discussions with participants in the intervention and telephone interviews with those who left the program.