The purpose of this study was to determine whether criminal history risk moderates the effect of probation on future reoffending. A sample of 327 participants from the 1997 National Longitudinal Survey of Youth (NLSY97) who had been on probation were compared with 327 propensity score matched members of the NLSY97 who had been arrested but not placed on probation. Probation and arrest data analyzed between 1999 and 2008 failed to support the presence of an overall effect for probation. When the sample was divided into higher criminal history risk (one or more prior arrests) and lower criminal history risk (no prior arrests), however, probation was found to reduce recidivism in the lower criminal history risk group but not in the higher criminal history risk group. Accordingly, probation appeared to have a small but significant ameliorative effect on future offending in lower criminal history risk offenders.