Correctional facilities in the US are considered the largest provider of mental health services.1 The Sozosei Foundation is tackling the question—"What can be done to accelerate solutions so that we eliminate the inappropriate use of jails and prisons for mental health care?” But tackling the criminalization of mental illness is complex and there is no single solution or ‘magic bullet’ to eliminate the use of jail or prison for the treatment of people with mental illness. Identifying effective solutions is difficult, in part, due to the limited availability of data needed to evaluate whether solutions work.

To understand the Sozosei Foundation’s approach to impact, a team from the RAND Corporation interviewed grantees, representatives from partner organizations and thought leaders; reviewed scientific and grey literature; and met bi-weekly with the Foundation’s Executive Director. This document summarizes what the RAND team learned about the Foundation’s approach to impact and an evaluation strategy that aligns with this approach.