This study examines 5225 out-of-treatment crack users and drug injectors drawn from five different geographic areas to examine selected factors associated with homelessness. Of these crack users, 27% considered themselves undomiciled, and 60% had previously entered some type of drug treatment. Logistic regression found that substance abusers who were married, female, and persons of color were less likely to be without a home when other variables were controlled. Trading sex for money and perceived chance of getting acquired immunodeficiency syndrome (AIDS) were associated positively with homelessness, while participating in methadone detoxification and methadone maintenance programs seemed to offer some protection from homelessness.