Meet Sam Tsemberis. He's all but solved chronic homelessness. His research, which commands the support of most scholars, has inspired policies across the nation. The results have been staggering. Late last month, Utah, the latest laboratory for Tsemberis's models, reported it has nearly eradicated chronic homelessness. Phoenix, an earlier test case, eliminated chronic homelessness among veterans. Then New Orleans housed every homeless veteran. Homelessness has long seemed one of the most intractable of social problems. For decades, the number of homeless from New York City to San Francisco surged - and so did the costs. At one point around the turn of the millennium, New York was spending an annual $40,500 on every homeless person with mental issues. Tsemberis ... unfurled a model so simple children could grasp it, so cost-effective fiscal hawks loved it, so socially progressive liberals praised it. Give homes for the homeless, and you will solve chronic homelessness. Success begat success. The federal government tested the model on 734 homeless across 11 cities, finding the model dramatically reduced levels of addiction as well as shrank health related costs by half. Adults who have experienced chronic homelessness may be successfully housed and can maintain their housing," the report declared. Utah's Gordon Walker, explain[s] how his state succeeded at eliminating homelessness - and saved millions, "It was costing us in state services, health-care costs, jail time, police time, about $20,000 per person. Now, we spend $12,000 per person."