CBT has been combined with other empirically supported treatments for alcohol and drug use disorders, such as Motivational Interviewing (MI) and Contingency Management (CM), as a strategy to bolster early treatment engagement and adherence. Several studies have investigated the combination of CBT and MI for various drugs of abuse, including amphetamines (Baker et al., 2005), cocaine (McKee et al., 2007; Rohsenow et al., 2004), methamphetamines (Bux & Irwin, 2006), and marijuana (Babor, 2004; Dennis et al., 2004). Although the findings have been mixed with respect to additive effects on drug use outcomes, there is some evidence to suggest that adding motivational enhancement to the early stages of CBT can be effective at increasing motivation and improving retention in treatment. Also, given that CM has strong immediate effects on substance use that tend to weaken after the contingencies are terminated (Prendergast, Podus, Finney, Greenwell, & Roll, 2006), while CBT tends to have more modest effects initially but is comparatively durable, there have been several investigations evaluating various combinations of CBT and CM. Results have largely indicated that CM is associated with
