Substance use disorders (SUDs) are among the most prevalent psychiatric disorders. According to the results of the recent National Epidemiologic Survey on Alcohol and Related Conditions (Grant et al., 2004), about 1 in 10 adults surveyed met DSM-IV (American Psychiatric Association, 1994) diagnostic criteria for an SUD in the previous 12 months. The sheer numbers of those affected suggest a high demand for SUD treatment services, as confirmed in recent surveys of need for treatment programs (e.g., Department of Health and Human Services, 2004). A variety of treatment orientations are represented among the programs available for those seeking treatment for an SUD in North America or Europe today. Common substance abuse program treatment orientations include Alcoholics Anonymous/12-Step, Therapeutic Community, Insight-Oriented, Rehabilitation, Dual Diagnosis, Medical/Disease Model, Marital/Family Systems, and Cognitive-Behavioral (Swindle, Peterson, Paradise, & Moos, 1995). As scientific evidence supporting the efficacy of cognitive-behavioral approaches has accumulated over the last 20 years or so, increasingly the alcohol and drug abuse treatment field has been shifting practices to include cognitive-behavioral techniques within their treatment programs. While medical/disease-based programming continues to predominate the substance abuse treatment field, cognitive-behavioral programs are one of the most commonly employed therapeutic orientations within this field today (e.g., Swindle et al., 1995). This special issue consists of a set of five articles that present reviews of the history, efficacy, and recent developments with respect to five specific subtypes of cognitive-behavioral treatment for SUDs: relapse prevention (Witkiewitz, Marlatt, & Walker, this issue), guided self-change (Sobell & Sobell, this issue), behavioral couples therapy (Fals-Stewart, O'Farrell, Birchler, Cordova, & Kelley, this issue), the community reinforcement approach (Meyers, Villanueva, & Smith, this issue), and dual diagnosis treatment approaches that employ cognitive-behavioral techniques (Conrod & Stewart, this issue). One important broad trend in substance abuse care that emerged about two decades ago and that continues today has been an increased emphasis on treatment outcome and process evaluation (e.g., examining the relative effects of different treatment orientations, and the relative benefits of different treatment components) (Moos & Finney, 1995). There is now indisputable evidence for the efficacy of cognitive-behavioral treatments for SUDs. Each of the articles contained in the current special issue reviews evidence that clearly establishes that these five subtypes of cognitive-behavioral SUD treatment produce significant improvements in SUD symptoms. Several large-scale studies examining predictors of outcome across various substance use treatments including cognitive-behavioral (e.g., McLellan et al., 1994; Ouimette, Gima, Moos, & Finney, 1999b; Project MATCH Research Group, 1997) are now indicating that theoretical orientation of the treatment is not a strong determinant of SUD treatment outcome. Now that several empirically supported treatments have been clearly established to be generally equally effective, researchers have begun moving in the direction of trying to understand what these treatments have in common. These attempts to identify the mediators of change that are common to these various interventions versus those that are potentially specific to individual approaches will bring the field forward. The articles presented in this issue provide a set of thorough, up-to-date reviews of the established efficacies of the various interventions. All contributions then go beyond the issue of efficacy by exploring potential active ingredients and mediators of change specific to each theoretical perspective. Given the cognitive focus of this journal, it appears appropriate to comment on the potential cognitive mediators of change within each of the five particular treatment approaches reviewed herein. …