The presentence investigations, crime reports, alcohol histories, and prior convictions of all felons convicted from the reservation from 1978 through 1988 were collated for the study. Of 62 convicted felons during the reporting period, 71 percent committed violent crimes, 25.8 percent property crimes, and the rest were not easily classified. Over 80 percent of the offenders were male with an average age of 28; almost one-third had prior felony convictions. Over 77 percent had three or more alcohol-related arrests and over 27 percent had three or more prior convictions for assaultive behavior. In examining the role of intoxicants in these crimes, the research found that almost 70 percent of the offenders were under the influence of alcohol when they committed their crimes; in only 18 percent of the violent crimes were the felons sober. Even in 37.5 percent of the property crimes, the offender was under the influence of alcohol. Although most alcohol abusers deny the disease, 63 percent of the defendants in this study admitted their alcohol problems, and 59 percent of those had undergone some type of treatment. This might suggest either the intractability of alcoholism within the Native American population or the greater efforts being made to expose the reservation's alcoholics to treatment. However, 15 defendants convicted of alcohol-related offenses denied their alcoholism, despite the fact that most of them had arrest histories of alcohol-related convictions and arrests. In the twelve homicide and manslaughter convictions in the study, 11 of the perpetrators had been under the influence of alcohol. The probation officer working on reservations must deal with limited treatment resources, a background of poverty and unemployment, genetic predisposition to alcoholism, and social and cultural factors that exacerbate the problem. 2 tables.