The study has three aims. Aim 1 involves the development of an evidence-based 12-step facilitation toolkit curriculum. Toolkit structure and content is grounded in theory and empirical findings, and incorporates feedback from 12-step facilitation experts and individuals with a history of substance abuse. Aim 2 consists of implementing the resulting five-module Toolkit in a multi-site randomized controlled trial using a pre-/post-Toolkit training design that includes 1- and 6-month post-training assessments. Group counselors employed at community-based outpatient and inpatient substance abuse treatment programs will be randomly assigned to a Toolkit or treatment-as-usual condition. Data obtained from audiotaped sessions will identify between group differences in counselor adherence to 12-step content and skillfulness. Additional data will be collected on counselor satisfaction, 12-step attitudes and beliefs, and 12-step knowledge, as well as on Toolkit acceptability, feasibility, and short-term sustainability. Aim 3 will determine whether exposure to the Toolkit curriculum results in stable 12-step involvement and decreased self-reported substance use among clients.