This study examined whether the use of alcohol and drugs, and psychiatric problems discriminate between offenders and other homeless veterans; investigated the types of offenses committed by homeless veterans that were alcohol and drug abusers; and determined what factors discriminated between non-offenders, nuisance offenders, and felony offenders among veterans that were abusing alcohol and other drugs. A random sample (188) was selected from the population in the Domiciliary program for homeless substance abusers at a Veterans’ Administration Medical Center in the South. All study participants were interviewed on 2 separate days within the first 3 weeks of arrival in the program unit. The Addiction Severity Index (ASI) was administered, as well as the Multi-Problem Screening Inventory (MPSI). The results showed that most homeless persons suffered multiple problems. In this study, 24 percent had attempted suicide, 42 percent had suicidal thoughts, 45 percent were depressed, 41 percent had committed crimes in the past year, 27 percent committed nuisance offenses in the past year, and 40 percent had been in a psychiatric hospital prior to being interviewed in this project. About 40 percent of the homeless males committed felonies. The findings showed that intensity of alcohol abuse and of other drug abuse, number of psychiatric hospitalizations, suicidal thoughts, and depression discriminated between non-offenders and offenders. Studies with large samples using procedures such as log-linear analysis are needed to determine the actual overlap between these problems among homeless persons. This study suggests that the integration of alcohol, drug, and mental illness services should include assessment and intervention approaches for persons that commit nuisance and felony offenses. There is a need for a classification scheme that guides differential treatment of the various patterns of interlocking problems suggested by this study. 5 tables, 74 references