In March of 1985, the Massachusetts Department of Correction opened Longwood Treatment Center, the state's first minimum security prison designed exclusively to detain and provide alcoholism education and treatment to multiple drunken driving offenders. A process evaluation of the program revealed that the program was implemented as planned and served the intended target population. Preliminary outcome measures revealed that 6% of program participants were returned to prison within one year of release, compared to a department wide recidivism rate of 25% and to a rate of 19% for other low security institutions similar to Longwood. Issues raised from the evaluation resulted in recommendations that aftercare services be strengthened, counseling and correction staffs be restructured, and operating costs be reevaluated. The findings suggest that the program was effective in reducing recidivism among multiple drunk drivers and in impacting on offenders' alcoholic behaviors. This evaluation report of the Longwood Program includes an overview of the program and sections on research methodology, historical developments, the program philosophy, the population served, a description of the program in operation, outcome measures of program effectiveness, a program cost analysis, and conclusions and recommendations. (Author/NB)