The California Substance Abuse and Crime Prevention Act of 2000 (SACPA) requires that an offender convicted of a nonviolent, drug related crime be offered probation and community based drug treatment in lieu of jail or prison. UCLA conducted three studies assessing the cost implications and benefit cost ratios of SACPA. Each showed that SACPA yielded cost savings to state and local governments. Study 1, using a before SACPA comparison group and all first year SACPA eligible offenders, found a net savings of $2,861 per offender (N=61,609), yielding a benefit cost ratio of nearly 2.5 to 1 (i.e., $2.50 was saved for every $1 invested). Study 2 determined that SACPA participants who completed the program achieved a benefit cost ratio of approximately 4 to 1 (i.e., "completers" saved $4 for every $1 allocated). Study 3 found that cost savings for the second year of SACPA were similar to Study 1, with a benefit cost ratio of 2.3 to 1. Three conclusions result from the cost analyses:SACPA substantially reduced incarceration costs? SACPA resulted in greater cost savings for some eligible offenders than for others? and SACPA can be improved. Recommendations encompass actions within and across multiple areas: Statewide collaboration and coordination, offender eligibility criteria and alternative practices for high-cost offenders, systems integration, criminal justice, drug treatment, and strategic planning.