The purpose of this study is to assess Motivational Interviewing (MI) to improve treatment engagement and outcome in subjects seeking treatment for substance abuse.

Participants seeking treatment at the participating CTPs will be randomly assigned to either "standard" or "MET/MI" treatment, with a 1- and 3-month follow-up. Primary outcome measures will include (1) treatment retention (e.g., number of sessions/weeks completed, the rate of patients completing 3 or more subsequent sessions, and (2) substance use (e.g., urinalyses, days of opioid, cocaine, marijuana, alcohol use, rates of abstinence). Secondary outcomes will include motivation, psychosocial functioning, HIV risk behaviors, treatment utilization, and patient satisfaction. Process assessments will include measures of the working alliance as well as therapist adherence/competence ratings which will evaluate how effectively MET/MI was implemented. Participating CTPs will implement one of two independent protocols, depending on which is the best suited or feasible for the intake procedures at their clinic. Thus, following an invitation to participate, explanation of the study, and provision of informed consent, patients would complete a brief assessment battery followed by either:1) Random assignment to 3 individual sessions of standard treatment (treatment as usual) at the program versus 3 individual sessions of MET; or 2) Random assignment to 1 individual standard assessment/evaluation session.

Inclusion Criteria:

Individuals will be eligible for the protocol who: a)Are seeking outpatient treatment for any substance use disorder. b)Are 18 years of age or older. c)Are willing to participate in the protocol (e.g., to be randomized to treatment, be contacted for follow-up assessment, to have their sessions audiotaped). d)Are able to understand and provide written informed consent.

Exclusion Criteria:

Individuals will be excluded who: a)Are not sufficiently medically or psychiatrically stable to participate in outpatient treatment. b)Are seeking detoxification only, methadone maintenance, or residential inpatient treatment.