The impact of mental illness, comorbid substance abuse, and medication nonadherence, coupled with disjointed psychiatric and social services, conspires to a disproportionately high rate of psychiatric disorders among people who are homeless in the United States. This article reviews the prevalence of homeless among the mentally ill as well as the prevalence of mental illness among the homeless and details barriers in access to care and the solutions that have been attempted. The need and solutions to introduce a new generation of physicians and allied health care workers to the unique health care needs of the homeless population are highlighted.