Three million Americans living in poverty are either a mother who has experienced depression or a young adult who has experienced serious psychological distress during the past year. Untreated mental health needs have significant consequences for mothers and young adults as well as their families. This is especially true for low-income people. It is essential to create policy that better meets their mental health needs to ensure their healthy development and long-term success. This report makes the case for CLASP's new foundation-funded effort to strengthen Medicaid, mental health, and human services policy at the federal and state levels to improve outcomes for families and young adults living in poverty. The goals of this initiative are to: (a) develop frameworks for identifying and treating maternal depression among parents of young children as well as improved access to high-quality mental health supports for youth; and (b) help a small number of selected states implement important aspects of the two frameworks. CLASP is uniquely positioned to bridge diverse stakeholders, analyze and identify policy opportunities, and support states interested in advancing this policy agenda. Across numerous fields, policymakers and stakeholders must work together to foster equitable health and economic outcomes for low-income mothers and young adults living in poverty. This work is essential to building systems support all low-income people's mental health and wellness.