Contrasts person-centered and structural explanations for homelessness. Methodological problems in studies of homeless people tend to exaggerate the role of individual deficits as causes of homelessness. A review of data on the distribution of poverty and of inadequate and unaffordable housing, with special emphasis on families, suggests the importance of structural causes. Data from 700 families requesting shelter and 524 families randomly drawn from the public assistance case load in New York City provide more support for a structural than for an individual deficit model. Individual demographic factors are also important. Implications are drawn for research and action by psychologists.