The U.S. Department of Housing and Urban Development (HUD) is pleased to present the 2009 Annual Homeless Assessment Report (AHAR), the fifth in a series of reports on homelessness in the United States. The reports respond to a series of Congressional directives calling for the collection and analysis of data on homelessness. The AHAR reports provide the latest counts of homelessness nationwide—including counts of individuals, persons in families, and special population groups such as veterans and chronically homeless people. The report also covers the types of locations where people use emergency shelter and transitional housing; where people were just before they entered a residential program; how much time they spend in shelters over the course of a year; and the size and use of the U.S inventory of residential programs for homeless people. With the 2009 AHAR, we now have three complete years of data on the numbers and characteristics of sheltered homeless people, how they became homeless, and how they used the homeless services system. This is important, because we can begin to see discernable trends in homelessness, including the effects of the recession and of changes over time to the homeless services system. The 2009 AHAR also marks continued improvement in both sources of estimates of homelessness used in the reports. A larger number of communities are reporting Homeless Management Information System (HMIS) data to the AHAR, which is used in the analysis of patterns of homelessness over a year’s time. In 2009, 334 communities—representing 2,988 counties and 1,056 cities—reported usable HMIS data to the report, a sizable increase from last year’s report (222 communities). At the same time, the point-in-time (PIT) counts essential for estimating the numbers and characteristics of all homeless people, both sheltered and unsheltered, are improving as communities use more rigorous methodologies for conducting the counts. For the first time, this 2009 AHAR includes information from in-person interviews with local service providers located in nine communities nationwide. This qualitative information provides a contextual backdrop for understanding how homelessness is changing.