Most racial/ethnic minority adults have higher rates of type 2 diabetes (T2DM) and its physiologic and behavioral risk factors than their White counterparts. Lifestyle changes can reduce the risk of T2DM in persons with impaired glucose tolerance. This study will test the effectiveness of a lifestyle program to increase physical activity, reduce weight, and improve diet, offered in community-based settings to primarily lower income, minority (African American, Latino, South Asian) adults aged 40+ with "pre-diabetes" (fasting glucose 100-125 mg/dl). Existing public health department staff and community peer educators will provide outreach and conduct the program. The original program, CHAMPS, increased physical activity and reduced weight in persons aged 65-90 in a randomized trial and was diffused in minority communities. CHAMPS provided education and behavior change support to develop a personalized, choice-based regimen that accounted for participants' health, preferences, and readiness to change. Our aims are to: 1) adapt CHAMPS to: a) augment its dietary component; b) meet the needs of our target population, and c) be integrated into the infrastructure of a city and county public health department; and 2) evaluate the effectiveness of an adapted 6-month program (and 6 month maintenance phase) with a 1-yr randomized controlled trial (n=330), and 3) describe costs to health departments of program start-up and provision. The primary outcome is fasting plasma glucose; secondary outcomes are other diabetes risk factors (body weight, waist circumference, physical activity, insulin resistance, blood pressure, dyslipidemia, and the metabolic syndrome) and health-related quality of life. Steps to identify eligible persons include: educational outreach (n=10,903), diabetes risk appraisal (n=8,177), and pre-diabetes screening (n=785) in neighborhoods with health disparities. Mechanisms by which the program reduces physiological risk at 1 year will be explored, e.g., whether changes in fasting glucose are mediated by weight loss or inflammatory factors. This research combines a practical program conducted in real-world community settings with the scientific strength of a randomized trial design. By augmenting the services that public health departments already offer to help prevent T2DM in some of the nation's most at risk groups, this project could serve as a model to potentially narrow the gap between knowledge and practice for diabetes prevention.