Compared to the cocaine-dependent patients, the marijuana-dependent patients were younger and less likely to be dependent on alcohol or other drugs. Both groups had similar rates of comorbid anxiety and affective disorders. Marijuana-dependent patients had fewer dependence symptoms, but a higher percentage of them had withdrawal symptoms. Although marijuana-dependent patients had less exposure to treatment, the difference was not statistically significant. Motivation for change was similar for both groups; however, cocaine-dependent individuals were more motivated for treatment. These findings suggest that although the desire to change was similar for both groups, marijuana-dependent patients might not have had as strong a belief that continued drug use would have a strong negative impact on their lives; therefore, they were more ambivalent in feeling that their drug-dependence was a serious problem. All of the participants were recruited for the study through advertising in the New York City area, and all were involved in outpatient treatment related to either marijuana or cocaine use. In addition, they met accepted criteria for cocaine dependence or marijuana dependence. They were between the ages of 18 and 60. Persons with a psychotic or bipolar disorder were excluded, along with those who were physiologically dependent on opiates, sedatives, or alcohol. The Circumstances, Motivation, Readiness for Treatment Scale and the University of Rhode Island Change Assessment measured motivation for change and motivation for treatment, respectively. 4 tables and 42 references