Amity RighTurn is a voluntary, 9- to 12-month intensive therapeutic community in-prison substance abuse program for 200 male inmates, with continuation services for up to 60 inmates paroled to San Diego County. The program, which enrolled its first participants in November 1990, reached maximum capacity in March 1991. Inmates participate in 20 hours of programming per week; it consists of group sessions, individual counseling, educational seminars, intensive workshops, video replay, and employment. Urine testing is conducted by Department of Corrections staff. During the 11-month period of November 1990 through September 1991, Amity provided operations in the areas of recruitment, counseling, seminars, intensive workshops, and video replay. This report provides data on each of these activities. The evaluation found signs of program success. They include the achievement of program goals, program completion rate, overall program progress, participant satisfaction with services, urine test results, prison behavior, the effect of the program on participants, the need for aftercare, and program costs. Data are provided for each of these areas. 26 tables, 4 figures, 11 graphs, and appended supplementary information