The Treatment Evaluation Project was established to evaluate the feasibility of using behavioral treatment in conjunction with methadone maintenance to improve the effectiveness of methadone treatment. Over 100 outpatients were accepted into treatment and randomly assigned to one of four behavioral treatment modalities in addition to the usual methadone maintenance procedures. Sixty clients participated in treatment for six months or more. Treatment was provided by a paraprofessional counseling staff under the supervision of professionals. Client outcomes were evaluated and compared in terms of (1) urinalysis results for illicit drug use; (2) employment records, (3) arrest records, and (4) treatment retention and attendance. The assigned modality of behavioral treatment/counseling was found to bear no relationship to these outcomes. Despite the lack of differentiation in the outcomes of the overall clinical evaluation, data from specific experiments conducted during the course of the project indicate that both contingency management procedures and the emotionally-based behavior therapy procedures may have utility in the treatment of drug abuse. It is suggested that what is needed is more rigorous and systematic basic research with specific procedures and precisely focused outcome measures in order to develop an empirical base for the behavioral treatment of narcotics dependence. (Author)