Because reconviction rates vary according to length of sentence and offender age, samples of young (under 21 years old at release) and adult (21 years old and older at release) offenders were drawn from parolees released from each of three broad sentence categories: short sentences (less than 3 years), medium sentences (3 years and under 5 years) and long sentences (5 years and longer). A minimum sample of 200 parolees in each group was selected. Each parolee's official record of postrelease offenses was examined. Young offenders with long sentences were significantly more likely to reoffend (38.7 percent) than any other group, and short-sentence adult offenders were the least likely to reoffend (14.8 percent). For all three sentence groups, offenses committed were less serious than those for which they had been originally imprisoned. Parolees were more likely to reoffend during the first quarter of their parole period. 3 tables, 4 references.