The inmate sample, which consisted of 50 drug and alcohol offenders and 50 other offenders, was drawn from county inmates admitted during 1987. Data on inmate personal characteristics covered demographic and personal data, medical and substance abuse histories, and discipline reports (number and type). Alcohol was the most prevalent abused substance among the inmates, but a significant percentage abused a variety of controlled substances, with many being polysubstance abusers. The combination of educational, occupational, and substance abuse problems exacerbates inmate problems. Interventions must be coordinated to meet the multiple needs of the inmates. With many short-term inmates, there have been no case plans or service coordination. Information developed as part of presentencing probation assessments, if passed along with the prisoner's record, could be used to speed up classification and the development of case plans to make them available for short-term inmates. Substance abusers contribute to jail overcrowding. The diversion of less serious drug offenders for community treatment could relieve overcrowding. 10 references, appended code sheet, appended supplementary information, 15 tables.