We led the Toronto arm of the Mental Health Commission of Canada At Home/Chez Soi study (2009-13), the largest randomized controlled trial in history to evaluate solutions to address homelessness. Our success testing the “Housing First” approach influenced the province of Ontario to set a goal to end chronic homelessness within the next ten years. Citing our evidence, the Ontario Ministry of Health and Long-Term Care also committed to invest $4M long-term funding to sustain housing and support to At Home participants in Toronto, and the federal government committed resources to scale up Housing First interventions across the country.