The document discusses the nature and extent of homelessness in America. It notes that homelessness has increased, particularly among families with children, as many cannot find affordable housing. There are various subgroups among the homeless population, including the "hidden homeless" who are difficult to count because they live in places like motels or vehicles or double up temporarily with others. Common causes of homelessness include mental illness, poverty, drugs and alcohol. At any given time in 2009, over 124,000 individuals were chronically homeless, with veterans, those with HIV/AIDS, unaccompanied youth and victims of domestic violence making up significant percentages. The McKinney-Vento Act provides remedies focused on preventing and responding to homelessness.