The data of this study were derived from comprehensive interviews of 311 women and 949 men residing in the New York City public shelters for homeless adults during the summer of 1987. Interviews, guided by a 57 page interview protocol, were conducted by thoroughly trained interviewers who had worked in agencies and service systems focused on mental disorders, child abuse, substance abuse and problems of homeless people. Included in the content of the interview were seven dichotomous measures of substance use, substance abuse and mental disorder. A typology of ten groups comprised of individuals with similar profiles on the seven measures served as the independent variable. Three pairs of dependent variables were suicide attempts and current thoughts of suicide, a need for medical services reported by shelter residents and by their interviewers, and disclosure of a drug problem and a need for help in treating it. Consistently meaningful associations between group memberships and the 3 pairs of dependent variables, and 16 measures of health status in previous work, were interpreted as evidence for predictive validity of the typology.