For millions of people in the United States, the struggle for stable housing both shapes and is shaped by numerous factors, such as employment opportunities and wages, housing market dynamics, access to health care, financial stability, and involvement with the criminal justice system. In the United States, more than 500,000 people experience homelessness on a given night, and 1.4 million people pass through emergency shelters in a given year. Many more individuals experience housing instability in other, often uncounted forms, whether living doubled up with friends or family, living in temporary accommodations such as motels, or living under threat of eviction.

The scope and complexity of housing instability and homelessness in the United States highlight the need for rigorous evidence on the effectiveness of strategies to prevent and reduce homelessness. Each year, billions of dollars in public financial resources are devoted to combatting housing instability, between federal expenditures and additional spending within local jurisdictions. It is critical that these resources fund policies and programs that will efficiently help to end homelessness.

In the past few decades, many organizations have shifted the types of services offered to individuals and families experiencing housing instability to prioritize immediate housing, referred to as a Housing First approach. Evidence played a fundamental role in building support for this new model from the beginning, with several randomized evaluations demonstrating that a Housing First approach could more effectively house people experiencing chronic homelessness than shelter-based approaches.

While the rigorous evidence on the Housing First model and other approaches to reducing and preventing homlessnesss provides a start, open questions remain as to effectiveness of the current organization of homelessness programs in North America. How can rigorous evaluation continue to drive improvements to policies and services aimed at helping people experiencing housing instability access and maintain stable, affordable housing?

To answer this question, J-PAL North America released an Evidence Review summarizing results from 40 rigorous evaluations of 18 distinct programs related to homelessness prevention and reduction. The publication focuses mainly on questions that can be answered through rigorous impact evaluation methods and outlines a research agenda for additional evaluation based on a recently released academic working paper on homelessness, “Reducing and Preventing Homelessness: A Review of the Evidence and Charting a Research Agenda,” by William Evans and David Phillips of the University of Notre Dame and Krista Ruffini of the Goldman School of Public Policy at the University of California at Berkeley.

The body of evidence suggests some areas of promise, but demonstrates that additional research on the effectiveness of other strategies to reduce homelessness is needed.

First, homelessness prevention is an area that demands more rigorous evaluation. An existing body of research demonstrates that emergency financial assistance and more comprehensive interventions that provide a range of financial assistance, counseling, and legal supports can prevent homelessness among families at risk of eviction. Additionally, legal representation for tenants at risk of losing their homes holds promise for reducing evictions. However, more research is needed on how prevention programs can best be delivered and targeted towards those most in need.

Second, permanent supportive housing programs, which provide long-term housing support and wrap-around services with no preconditions, can increase housing stability for veterans and individuals with severe mental illness. Based on the body of rigorous evidence behind Housing First approaches to homelessness reduction, many organizations have shifted toward this model of intensive assistance, and away from the traditional model of requiring preconditions, such as sobriety and employment, before obtaining permanent housing. However, there has been little rigorous evaluation of the impact of permanent supportive housing programs for other groups of people.

Third, although rapid re-housing is a potentially cost-effective solution to provide immediate access to housing, there is limited evidence on the impacts of rapid re-housing on long-term housing stability. Rapid re-housing aims to house people experiencing homelessness as quickly as possible by providing short-term rental assistance and services to help households overcome barriers to long-term housing stability.

Fourth, subsidized long-term housing assistance in the form of housing vouchers helps low-income families avoid homelessness and stay stably housed. The federally subsidized housing program with the most rigorous evidence to date is the Housing Choice Voucher program. Also known as Section 8, the program provides eligible low-income households with rental assistance to pay for private-market housing in units that they select.

The publication also identifies existing gaps in the literature and outlines key open questions about the effectiveness of strategies to reduce and prevent homelessness to consider going forward. For instance, it is important to rigorously test the impact of existing programs with a limited evidence base, such as rapid re-housing. Additional questions remain on how homelessness programs and services affect non-housing related outcomes and how best to design and target services to maximize potential impact.

To help answer these questions, J-PAL North America’s work on homelessness seeks to expand the base of rigorous evidence on strategies to reduce and prevent homelessness and promote housing stability by partnering directly with nonprofits and government agencies.



Organizations interested in being paired with researchers to rigorously evaluate strategies to ameliorate homelessness are encouraged to contact project manager Rohit Naimpally. J-PAL North America may be able to offer technical assistance, matchmaking with researchers, and funding to cover the cost of an evaluation. For more information, please see our Housing Stability Evaluation Incubator.

J-PAL North America is a regional office of the Abdul Latif Jameel Poverty Action Lab (J-PAL), a global research center based at MIT.