The purpose of this study was to determine whether patient education programs were effective at improving knowledge of substance abuse among dual-diagnosis patients. Adult patients at a general psychiatry hospital were identified for a history of substance abuse. Of the 51 patients included in the study, 25 were on forensic units, 7 were in a private ward, and 19 were on the public unit. Patients were given a pretest at the beginning of the study and received an identical posttest prior to discharge or at the end of the study. The patients on the public unit received up to 16 h per week of Alcoholics Anonymous meetings, alcohol/drug education meetings, group therapy, and other forms of intervention. These patients demonstrated statistically significant improvements between pretest and posttest scores, while those on the forensic units who received only 2 h of intervention per week did not show improvements in substance abuse knowledge. These and other findings have been used to improve education programs for our dual-diagnosis patients across the institute.