Although gender-related issues are often cited as playing an important part in determining patterns of illicit drug use, little is known about the differences between male and female drug users outside treatment settings. In the present study, 558 heroin and cocaine users recruited from a range of community settings were interviewed by Privileged Access Interviewers. The women were found to be younger than the men. Differences existed in their drug use; women used smaller amounts, for a shorter duration, and were less likely to inject than their male counterparts. No differences existed between treatment contact for the heroin users, but differences were found among the cocaine-using sample, with men being more likely to have contacted a treatment agency. Men were financing themselves through more criminal activities than women. Drug-using sexual partners were found to be an important influence over women's drug use, with most female injectors having been given their first injection by a male sexual partner. Structural differences in patterns of drug use found among female drug users and the influence of male sexual partners are likely to play an important role in determining appropriate treatment options for women drug users.