Objective: To assess the course and severity of substance-related disorder (SRD) in relation to gender. Design: Retrospective data on course were obtained for several indices of substance use, abuse, and related morbidity. Setting: Two university medical centers with alcohol-drug programs located in departments of psychiatry. Subjects: A total of 642 patients were assessed, of whom 365 (57%) were men and 277 (43%) were women. Methods: Data on course included demographic characteristics, family history of substance abuse, lifetime use, age at first use, years of use, use in the last year, periods of abstinence, and current diagnosis. Data on severity included two measures of SRD-associated problems (one patient rated and one interviewer rated), substance abuse versus dependence, self-help activities, and previous treatment. Resuits: Women were more apt to be homemakers; to have a sibling or, if married, a spouse who abused substances; to be less apt to have ever used hallucinogens or inhalants; to have used substances for fewer years; to have used cannabis and inhalants for fewer days in the last year; to have a lower rate of current cannabis abuse/dependence; to have fewer legal problems related to substances (especially driving while intoxicated [DWI] charges); to have fewer outpatient admissions to treatment; to have fewer admissions to substance abuse treatment (all categories together), fewer lifetime days in treatment, and lower overall treatment cost (for all categories of treatment together). Conclusions: These data confirm earlier reports of a shorter course, less deviant drug usage, and - if married - a substance-abusing spouse. In addition, we found higher rates of familial substance abuse and lower rates of lifetime admissions, treatment days, and total cost of substance abuse treatment. Homemaking responsibilities, a substance-abusing spouse, a male-oriented treatment system, and/or a more rapid course may reduce substance abuse treatment for women.