Homelessness is a complex social problem. Homelessness affects people of both genders and all ages and racial and ethnic groups; however, single men and children younger than five living in low-income families are disproportionally represented among the homeless population. A US government report estimates a one-day prevalence of close to 650,000 sheltered and unsheltered homeless people nationwide and a twelve-month prevalence of close to 1.56 million people using an emergency shelter or a transitional housing program. Homelessness intersects with an array of other social problems, including mental illness, substance abuse, domestic violence, child neglect and abuse, foster care, and criminal justice. Regardless of the personal vulnerabilities that put an individual at risk of homelessness, agreement is general that structural factors, notably the shortage of affordable housing, structural unemployment, and poverty, contributed to the emergence, growth, and persistence of homelessness during the late 20th and early 21st centuries. The complex and dynamic interplay of structural and individual factors has been documented in in-depth accounts of persons coping with homelessness through the use of different subsistence strategies. Public response toward homelessness and public policy for preventing or ending homelessness has evolved over time, representing an increasing acknowledgment of the multifarious nature of homelessness.
