There is a significant and growing number of adolescents who separate early from their families and become homeless. These youths are heterogeneous in terms of gender, race, ethnicity, and socioeconomic status, but the majority come from families that have been disruptive or dysfunctional in some way. Homeless adolescents are vulnerable to a variety of physical and psychologic problems related not only to their family histories but to the stressful environments in which they try to survive. Although numerous federal, state, and local programs have been developed to meet their needs for shelter, health care, and education, much remains to be done to ensure their healthy development and to prepare them for responsible life in the larger society.