Project Background: Over the next two decades, Veterans with psychotic disorders (i.e., schizophrenia spectrum disorders and affective psychoses) will age into older adulthood in unprecedented numbers. The challenges of treating this growing population and associated high costs will have profound implications for VHA. Older adults with psychotic disorders exhibit diminished physical and psychosocial functioning and are at increased risk for rapid functional decline and early institutionalization in nursing homes. Participation in structured exercise delays functional disability in older adults; however, older adults with psychosis exhibit low exercise participation. While peer-delivered exercise interventions for older adults promote initiation and maintenance of exercise and physical activity, there are no peer-delivered exercise interventions tailored to the unique needs of older adults with psychosis. The present study aims to fill this critical gap.