The program assumes that offenders will be 'shocked' by the realities of prison life and will reform as a result. Of two studies of outcomes of Ohio's shock probation program, one supported the program, but neither study compared outcomes between shock and regular probationers. Thus, performance or outcome rates were studied using an availability sample of all 1975 state-supervised shock (N=585) and regular (N=938) probationers, with a 2-year followup using the failure criterion of reincarceration in an Ohio penal institution. Chi-square and multivariate analyses were used, with type of probation the primary variable, and the independent variables of education, prior record, offense, and dependents were added to lessen statistical error possibilities. Successful performance in this combined sample was weighted toward the high school graduate, first offender, offenders committing a crime against the person, and those individuals with dependents. When the differences between the two groups were held constant, regular probationers had a 42 percent lower probability of reincarceration than shock probationers. One possible conclusion is that shock probationers might fail on regular probation at a significantly higher rate. Another is that perhaps incarceration is having some negative effect upon the performance of shock probationers. In either case further research is warranted. Tables, several references, and comments by the Superintendent of the Probation Development Section regarding this study are provided.