The purpose of this study is to perform a rigorous process and outcome evaluation of a last resort voucher strategy of linking persons in substance use disorder to recovery support services (RSS) by accomplishing the following specific aims: 

• Specific Aim 1: Conduct a process evaluation of the Kentucky Access to Recovery (KATR) linkage strategy to determine whether the KATR strategy is acceptable and accessible to vulnerable populations with illicit SUD who are linked to RSSs; identify barriers and facilitators to KATR implementation; and assess the extent to which the KATR strategy was implemented as designed.

• Specific Aim 2: Conduct an outcome and impact evaluation of the KATR linkage strategy.

• Specific Aim 3: Evaluate the long-term effectiveness of implementing vouchers as a linkage strategy in a population requiring RSSs when no other funding sources are available.