In this randomized, controlled study, 133 adults age 21 and older with serious mental illness (SMI) and poor physical fitness (BMI\>25, or \<10 minutes of exercise 2x over the past month) were randomized to either: a) In SHAPE Lifestyles (ISL) intervention or b) Health Club Membership and Education (HCME): consisting of a YMCA membership, educational materials on exercise and healthy diet, and an on-site introduction to the health club. The following three specific aims were addressed: 1) To compare ISL and HCME with respect to: a) participation in regular exercise and dietary change; (b) participation in preventive health care; and (c) improved fitness and health; (2) to compare ISL and HCME with respect to: (a) indicators of mental health and (b) personal self-efficacy; and (3) to explore differences in ISL and HCME with respect to (a) selected physical, metabolic, dietary, and community functioning secondary outcomes; and (b) the relationship of demographic variables and readiness to change to outcomes. ISL participants received a 6-month intensive program of one-to-one health mentoring, followed by a 3-month period of transitioning to self-directed individual and group programming, with assessments conducted at baseline, 3, 6, 9, and 12 months. If found to be effective, ISL will provide a practical approach to improving health, independent functioning, and longevity in disabled persons with SMI.