Diversion is granted on the day after court referral and typically within 2 days of arraignment. The defendant is ordered to report to his or her probation officer for a diversion orientation session within an hour of the grant of diversion. A drug court and two probation units handle drug diversion cases. Defendant compliance with the diversion contract is normally evaluated at a progress report hearing, and an incentives/sanctions point system establishes specific consequences for both compliance and noncompliance with the contract. The first 130 defendants referred to the FIRST diversion project between January 2 and February 8, 1991 and the first 130 defendants in a control group referred to diversion between January 1 and March 8, 1990 were evaluated. Evaluation results indicated that the imposition of an immediate probation supervision and treatment program substantially reduced the rate of recidivism. In addition, the immediate grant of diversion substantially increased the rate of appearance at court hearings, and defendants ordered to appear for their diversion orientation session within the shortest period after the diversion hearing had substantially better results complying with their diversion contract. By eliminating the need for formal diversion reports, the FIRST project saves Alameda County an estimated $300,000 per year. The diversion contract and supplemental evaluation data are appended. Tables