Look AHEAD (Action For Health in Diabetes) is a multicenter randomized clinical trial to examine the effects of a lifestyle intervention designed to achieve and maintain weight loss over the long term through decreased caloric intake and exercise. Look AHEAD is focusing on the disease most affected by overweight and obesity, type 2 diabetes, and on the outcome that causes the greatest morbidity and mortality, cardiovascular disease. This agreement is to support the costs of a Participating Clinical Center with the Look AHEAD clinical trial, located in the greater Phoenix area in Arizona under the aegis of the Phoenix Epidemiology and Clinical Research Branch.