The number of adult inmates incarcerated within California's Department of Corrections (DOC) grew from 39,373 in 1983 to 125,605 in 1994. Over the 1983-1992 period, the percentage of total inmates newly received from court with commitments for specific drug offenses increased from 10.9 to 35.9 percent. In response, five major drug treatment and recovery service programs are offered by the DOC. A sixth program, a therapeutic community for female drug addicts, was to have been implemented in April 1995. During fiscal year 1993-1994, the five programs provided drug treatment and recovery services to over 3,600 program participants, at a cost of about $10.3 million. The five programs provide community-based drug treatment services to male and female offenders in 11 counties which represent 74.4 percent of the parolee population. Over 80 community-based drug treatment and recovery service providers are contracted by the DOC. The referral and program placement process is described, and summaries of the five programs are included. Appendixes contain additional information on drug treatment services in California, HIV infection risk, and characteristics of drug treatment program participants. 19 tables