Poverty is the underlying cause of all homelessness. Structural changes within the American economy have had a profound impact on societies "bottom segment." No, homelessness is not caused by mental illness, addictions, or unemployment.
National Coalition for the Homeless: A national advocacy network committed to "ending homelessness". Provides facts about homelessness, references to research materials, a directory to homeless/housing organizations, the NCH newsletter and calendar, and information about legislation and policy.