The relationship between use of alcohol and street drugs and compliance with prescribed medication before admission to an acute psychiatric inpatient setting was studied in 42 schizophrenic patients, more than half of whom had a history of alcohol abuse or dependence. Most patients, even those without a history of alcohol abuse, admitted to drinking alcohol in the month before admission. Alcohol abusers drank significantly more often and drank significantly greater quantities than nonabusers. The majority of patients were noncompliant with prescribed medication before admission, and most of these patients specifically reported being noncompliant when drinking alcoholic beverages.