The evaluation study compared two samples, one entering the program after October 1978 and one entering the program before the program began. The first sample contained 1,541 probationers, and the second sample contained 2,437 cases. Only the high-risk cases from the pre-ISP period were included, since ISP focused on giving intensive suervision to probationers who were judged, using the instrument, to be at a high risk of an unfavorable probation outcome. Eight hypotheses concerning the program impact and five process variables were evaluated. The results were inconclusive. Efforts to strengthen the current risk assessment instrument were also unsuccessful. Data tables, 37 reference notes, and an extensive set of attachments consisting of data collection forms and other background materials are included. For the executive summary of this report, see NCJ 93927.