To assess the health insurance status of adolescents, the trends in adolescent health care coverage, the demographic and socioeconomic correlates of insurance coverage, and the role that insurance coverage plays in influencing access to and use of health care. Together, the results provide a current and comprehensive profile of adolescent health insurance coverage. We analyzed data on 14 252 adolescents, ages 10 to 18 years, included in the 1995 National Health Interview Survey. The survey obtained information on insurance coverage and several measures of access and utilization, including usual source of care, site of the usual source of care, indications of missed or delayed care, and use of ambulatory physician services by adolescents. We conducted multivariate analyses to assess the independent association of age, sex, race, poverty status, family structure, family size, region of residence, metropolitan resident status, and health status on the likelihood of insurance coverage. We conducted bivariate and multivariate analyses to ascertain how insurance coverage was related to each of the access and utilization measures obtained in the survey. We also examined trends in health insurance coverage using the 1984, 1989, and 1995 editions of the National Health Interview Survey. An estimated 14.1% of adolescents were uninsured in 1995. Risk of being uninsured was higher for older adolescents, minorities, adolescents in low-income families, and adolescents in single parent households. Compared with their insured counterparts, uninsured adolescents were five times as likely to lack a usual source of care, four times as likely to have unmet health needs, and twice as likely to go without a physician contact during the course of a year. Between 1984 and 1995 the percentage of adolescents with some form of health insurance coverage remained essentially unchanged. During this period, the prevalence of private health insurance decreased, while the prevalence of public health insurance increased. This study demonstrates the critical importance of health insurance as a determinant of access to and use of health services among adolescents. It also shows that little progress has been made during the past 15 years in reducing the size of the uninsured adolescent population. The new State Children's Health Insurance Program could lead to substantial improvements in access to care for adolescents, but only if states implement effective outreach and enrollment strategies for uninsured adolescents.adolescents, health insurance, access, Medicaid, SCHIP.