The adoption of performance-based management has been under consideration by addiction treatment funding agencies, and, recently, many state and county agencies have developed performance-based measurement/management systems in an attempt to improve their treatment system. This article describes one such effort in Los Angeles County, California. The Performance-Based Pilot Project linked treatment encounters (counseling sessions, drug testing, case management, and methadone dosing) with client outcomes (abstinence or reduced drug use at discharge) and longer lengths of stay in treatment. Eleven outpatient counseling programs and three narcotic treatment programs participated in the nine-month project. Results indicated that for both outpatient counseling and narcotic treatment programs, more sessions attended in the first 30 days was associated with better client outcomes and longer lengths of stay. Furthermore, in outpatient counseling programs, more group sessions during the first 30 days predicted abstinence or greater reductions in primary drug use; in narcotic treatment programs, more doses received during the first 30 days was correlated to longer treatment retention. This research implies that increasing the availability of counseling sessions for a client's first 30 days and engaging clients early is a promising area for program efforts to improve treatment outcomes and program performance.