Even as the national economy continues its slow-but-steady pace of improvement, data released by the Department of Housing and Urban Development in December revealed a small increase in the number of homeless Americans — a consequence of systematic housing shortages in many US metro areas that prevent wage gains from automatically generating increases in affordability.

Then a few weeks later came the annual ritual of the HUD Point-in-Time survey of the homeless population, in which HUD recruits volunteers around the country to go out and try to count up all the homeless people living in America. This year, HUD Secretary Ben Carson joined up, volunteering as part of a PIT crew that assembled at Union Station in Washington, DC, and announcing the disbursement of various federal grants to local anti-homelessness groups.

These counts are a critical element to making appropriate homelessness policy. And ultimately a systematic improvement of the situation is going to require big looks at structural barriers to building affordable units. But good policy also requires greater awareness of a fundamental research insight that is becoming a point of consensus among policy insiders — it’s cheaper to give homeless people homes to live in than to let the homeless live on the streets and try to deal with the subsequent problems.

Related How rising rents contribute to homelessness

Some early research on this produced truly mind-boggling results like a Central Florida Commission on Homelessness study indicating that the region was spending about triple on policing homeless people’s nonviolent rule-breaking as it would cost to get each homeless person a house and a caseworker. More recent, somewhat more careful studies, were a bit less enthusiastic about the cost-saving potential but still highly positive.

A 2017 RAND Corporation analysis of the Housing for Health program in LA County concluded that the county saved about 20 percent by putting people with complex mental health issues in supportive housing rather than relying on law enforcement and emergency room visits.

A 2015 randomized control trial of a housing-first approach across several Canadian cities saw essentially no change in money spent (Canada’s structurally lower health care costs are likely a factor here) but gains in quality of life and community functioning.

A separate randomized trial study in Toronto found that housing first was effective in combatting alcohol abuse disorders.

Earlier studies from Charlotte and Southeastern Colorado also show large cost savings from focusing on simply housing the homeless.

The general line of thinking behind these programs is one of the happier legacies of the George W. Bush administration. His homelessness czar Philip Mangano was a major proponent of a "housing first" approach to homelessness. And in the early years, it generated significant positive results with the rate of homelessness in America declining 17 percent between 2005 and 2012 despite the poor economic situation.

The more recent uptick in homelessness, however, is a reminder that housing scarcity remains a major problem in America. And yet when it comes to the chronically homeless, you don't need to fix everything to improve their lives. You don't even really need new public money. What you need to do is target those resources at the core of the problem — a lack of housing — and deliver the housing, rather than spending twice as much on sporadic legal and medical interventions.

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