OBJECTIVE To describe use of health services and self-reported access to regular and emergency care by homeless adolescents and street youth. METHODS Interviewer-administered surveys addressed use of health services, availability of sources of care for emergencies, and types of care sources used. An abbreviated version of the questionnaire used for youth in shelters was used for street youth. A nationally representative sample of 640 sheltered youth and a purposive sample of 600 street youth aged 12-21 years were interviewed. All data were collected in 1992. RESULTS Half of street youth and 36% of sheltered youth did not have a regular source of health care (p < or =.05). One-fourth of street youth and 18% of sheltered youth also reported serious health problems within the past year (p < or =.05). Street youth were more likely than sheltered youth to have used emergency treatment (36% vs. 29%; p < or =.05) and alcohol- or drug-related emergency treatment (25% vs. 13%; p < or =.05). Sheltered youth with a regular source of care were more likely to use nonemergency sites than those without a source of primary care (46% vs. 20%; p < or =.001). Few sheltered or street youth perceived shelter clinics, clinics for runaway youth, or free youth clinics to be available to meet their emergency care needs. CONCLUSIONS Significant numbers of homeless youth did not have a regular source of health care. Those who had a regular source of care were more likely to have continuity between routine and emergency care. Integration of health services with other agencies serving youth in shelters or on the street may improve access to care for those without a routine source of care and provide better continuity for these high-risk youth.