Contingency management (CM) is a demonstrably efficacious intervention for substance abuse and dependence. Substantial empirical research supports its efficacy in increasing treatment attendance and drug abstinence. Although CM protocols have employed a variety of reinforcers, they have almost exclusively relied upon non-cash privileges (e.g., take-home methadone doses), prizes, or vouchers that can be exchanged for goods or services. Despite the strong empirical support for CM, our research suggests that concerns relating to its cost and safety (e.g., potential for harm caused by rewards undermining intrinsic motivation or being sold to purchase drugs) have hindered its transfer to real-world practice. The exclusive use of non-cash CM likely stems from the untested assumption that clients will use cash incentives to buy drugs or engage in other high-risk behaviors. This assumption is problematic for two reasons. First, the use of non-cash incentives adds substantial costs and complexity to CM protocols. Second, the use of non-cash incentives may reduce the efficacy of CM interventions, as research suggests that cash may be a more effective reinforcer than vouchers. This study will examine practical and ethical issues relating to cash-based CM procedures. We are proposing to conduct a 3-group randomized study comparing the efficacy, cost-effectiveness, and ethics of a (1) voucher-based CM intervention, (2) cash-based CM intervention, and (3) non-CM intervention. Consenting cocaine-dependent clients attending a community outpatient treatment program will be randomly assigned to each condition in equal proportions. This study will measure outcomes related to (1) efficacy, including UDS confirmed abstinence and counseling attendance;(2) cost-effectiveness;and (3) ethics, including the effects on intrinsic motivation, drug use, and other high-risk behavior. This study will be the first to examine the differential efficacy, cost-effectiveness, and ethics of a cash- versus a voucher-based CM protocol in the treatment of drug dependence. This investigation not only will address practical issues pertaining to the transfer of CM interventions into community-based treatment programs, but also will begin to shed empirical light on many of the ethical criticisms that have been levied against the use of cash and CM interventions.