This project aims to determine whether Medicaid SUD and Reentry waiver programs increase access to SUD treatments, including MOUDs, and reduce overdose mortality. The goal is to move beyond simplistic dichotomous measures of waiver programs (waiver/non-waiver states), to a more robust multifaceted measure of key waiver policies, e.g., eligibility, benefits, delivery model reforms. Such a measure will generate more precise knowledge about which waiver policies have the most impact on access to treatment and outcomes. The project will measure the key policy dimensions of 43 existing SUD Medicaid Waivers, including the 19 Reentry Waiver Programs approved as of January 2025; conduct factor and cluster analyses to empirically determine  statistical variation across states on key policy dimensions (eligibility, benefits and delivery reforms); and merge the waiver database with key waiver variables for each state with Medicaid claims data from 2022 through 2028 to determine the impact of Medicaid waiver policy designs on access to SUD treatments and on outcomes.