In response to a Federal request for proposals for "Model Drug Abuse Treatment Programs for Non-Incarcerated Criminal Justice Populations," Amity -- a large, nonprofit drug abuse prevention and treatment agency -- approached the Pima County Probation Office to develop a day and evening education and treatment program for probationers. The program design included transplantation of essential treatment community program elements from the residential setting to a nonresidential setting, an escalating sanction design with appropriate supervision levels, assessment and support through a case management system, educational/vocational assessment and training, family support and counseling, health services coordination, intensive aftercare, and a location that allows all elements of the program to be conducted at one site. Over the 2 years of program operation, there have been several key changes. They have included increased efforts to maintain alignment between the Probation Department and Amity, increased intensity of services, and changes in eligibility requirements for probationers and the length of the program. Although the program is only 2 years old, the data collected and discussed in this report show it has been successful in intervening with probationers at high risk and who, during the program, continue to live and work in environments where drugs are readily available. The program has targeted racial and ethnic minorities disproportionately represented in the criminal justice system. 1 table and 1 figure