Evidence-based programs to prevent diabetes among high-risk individuals are less effective among those who also have mental health needs. This study involves developing and pilot testing the first adaptation of the landmark Diabetes Prevention Program lifestyle intervention to simultaneously treat prediabetes and elevated mental health symptoms. This project has large potential to impact public health, given that more than half of the U.S. adult population has either of these conditions, and is at risk for developing comorbid diabetes and mental illness.