The study sample included 4,523 Canadian offenders on conditional release who either successfully completed their parole or mandatory supervision in 1985 or had their parole or mandatory supervision revoked during the year. After additional criteria were applied, the final sample included 221 cases, 103 offenders on parole, and 118 on mandatory supervision. Parole releases were not differentiated from mandatory supervision releases on every dimension. There were no significant differences in terms of history of mental health problems, whether the index offense was sexual or assaultive in nature, whether the offender was under the influence of drugs at the time of the index offense, and whether there was an institutional record of administrative segregation. On the other hand, some clear differences did emerge. Less than half of the offenders released on parole had a history of substance use/abuse compared to those released under mandatory supervision. Further, a high percentage of offenders released under mandatory supervision had been under the influence of alcohol at the time of their index offense. Although most mandatory supervision cases had been under some form of community supervision at the time of the index offense, less than a third of those released on parole had a similar history. Those released under mandatory supervision were more likely to have been placed in protective custody and more likely to have been admitted to regional treatment or psychiatric centers. Study findings reconfirmed the Statistical Information on Recidivism Scale's ability to predict outcome on parole, but the scale's ability to predict mandatory supervision outcome is questionable. There was a consistent relation between identified need areas and both type of release and release outcome. 9 references, 11 tables, and 4 figures