Chronic homelessness is a highly complex social problem of national importance. The problem has elicited a variety of societal and public policy responses over the years, concomitant with fluctuations in the economy and changes in the demographics of and attitudes toward poor and disenfranchised citizens. In recent decades, federal agencies, nonprofit organizations, and the philanthropic community have worked hard to develop and implement programs to solve the challenges of homelessness, and progress has been made. However, much more remains to be done. Importantly, the results of various efforts, and especially the efforts to reduce homelessness among veterans in recent years, have shown that the problem of homelessness can be successfully addressed. Although a number of programs have been developed to meet the needs of persons experiencing homelessness, this report focuses on one particular type of intervention: permanent supportive housing (PSH). Permanent Supportive Housing focuses on the impact of PSH on health care outcomes and its cost-effectiveness. The report also addresses policy and program barriers that affect the ability to bring the PSH and other housing models to scale to address housing and health care needs.

In the United States, some populations suffer from far greater disparities in health than others. Those disparities are caused not only by fundamental differences in health status across segments of the population, but also because of inequities in factors that impact health status, so-called determinants of health. Only part of an individual's health status depends on his or her behavior and choice; community-wide problems like poverty, unemployment, poor education, inadequate housing, poor public transportation, interpersonal violence, and decaying neighborhoods also contribute to health inequities, as well as the historic and ongoing interplay of structures, policies, and norms that shape lives. When these factors are not optimal in a community, it does not mean they are intractable: such inequities can be mitigated by social policies that can shape health in powerful ways. Communities in Action: Pathways to Health Equity seeks to delineate the causes of and the solutions to health inequities in the United States. This report focuses on what communities can do to promote health equity, what actions are needed by the many and varied stakeholders that are part of communities or support them, as well as the root causes and structural barriers that need to be overcome.

In early 2007, the Institute of Medicine convened the Roundtable on Health Disparities to increase the visibility of racial and ethnic health disparities as a national problem, to further the development of programs and strategies to reduce disparities, to foster the emergence of leadership on this issue, and to track promising activities and developments in health care that could lead to dramatically reducing or eliminating disparities. The Roundtable's first workshop, Challenges and Successes in Reducing Health Disparities, was held in St. Louis, Missouri, on July 31, 2007, and examined (1) the importance of differences in life expectancy within the United States, (2) the reasons for those differences, and (3) the implications of this information for programs and policy makers.