Data for this cross-sectional study were collected from homeless and street youth in Minneapolis in 1998 and 1999. A convenience sample of youth aged 15-22 was recruited in settings where a high proportion of street youth were known to congregate. The sample of 203 homeless and street youth met the criteria for age, being homeless at least 1 month in the past year, and able to give informed consent for participation in the study. The 44-item questionnaire administered in interviews obtained the following information: age, race/ethnicity, education, amount of time on the street, and current living situation. Five questions were designed to determine the frequency of various risky sexual behaviors. Participants were also asked about their histories and results of testing for hepatitis B, hepatitis C, and HIV, as well as history of other sexually transmitted infections (STI's), pregnancy history, and current health needs. Cross-sectional analysis showed that 58.7 percent of males and 75.6 percent of females reported recent sexual intercourse. Of this group, one-third of the males and half of the females used no barrier method with at least one partner. Both gender (female) and race/ethnicity (non-Black) were associated with having intercourse without a barrier contraceptive method. Over one-fifth reported a history of "survival sex" or receiving money, drugs, clothing, shelter, or food in return for sex. The findings reveal significantly high rates of a number of risky sexual behaviors, indicating the need for targeted interventions with this highly vulnerable population. Educational efforts and services should be tailored to subgroups within this population. 2 tables and 46 references