This pilot study compares male offenders who were imprisoned with similar types who were placed on probation, to determine which program produces less subsequent criminal activity. It is based on 7,614 Wisconsin cases statistically comparable in origi nal disposition, county of commitment, type of offense com mitted, number of prior felonies, and marital status.Of the first felony offenders, those on probation had lower vio lation rates than those imprisoned and then paroled. For proba tioners and parolees with one prior felony, rates were about the same. For those with two or more prior felonies, violation rates were higher for probationers than for parolees.The frequency with which judges sentenced offenders to proba tion rather than incarceration varied directly with the extent to which the offenders were likely to violate. That is, judges tended to place those offenders with low violation rates on pro bation, the major exception being assault cases, where imprison ment was more frequently used.