Focusing on one major ISP juridiction, Bexar County, the study attempted to determine the extent of diversion occurring within the first 10 months of the program's operation and to provide a list of potential indicators which could be used on a statewide basis. A total of 187 cases of admission to the Bexar County ISP, covering the period from September 1, 1981, to early June 1982, was compared with 587 inmates who were admitted to the Texas Department of Corrections (TDC) between September 1, 1980, and August 31, 1981. Findings showed that over the 10-month period, the typical person admitted to less likely to be a minority, and more likely to be female than the TDC admittees. Findings also indicate there is no substantial change in the criminal history records of ISP probationers, with the exception of those offenders with prior records, where the average number of months of prior incarceration tended to decrease. Conclusions indicate that more serious offenders were not being placed in the ISP as the program progressed. Conclusions also indicate that there were only minor differences between the measured characteristics of the ISP and TDC. Under the criteria used in this evaluation, it is indicated that the ISP is diverting offenders from TDC. The estimated impact of the Bexar County ISP is a 60-percent diversion of cases from the district court and TDC over the life of the program. Tabular data are provided. (Author abstract modified).