The purpose of this study was to understand the sustainability of the At Home/Chez Soi (AHCS) project with respect to its wider impact on homelessness policy in Canada and internationally. Using a qualitative case study approach with 15 key informant interviews (with project leaders and decision-makers) and archival data, we examined the strategies adopted to achieve sustainability of the Housing First (HF) programs implemented during this demonstration project. In particular, we focused on the impacts that these strategies had on national policy. Four main themes emerged: (1) the importance of evidence that was both rigorous and contextually relevant; (2) the value of framing the evidence in a way to achieve maximum impact in the decision-making context; (3) the importance of strong researcher-decisionmaker relationships, which evolved through an integrated knowledge translation approach; and (4) the value of resources and expertise provided by key stakeholders. A subsidiary theme was the importance of timing. The change in federal policy was that as of 2015, the 10 largest Canadian communities were to allocate 65% of their federal funding to HF programs for chronically and episodically homeless persons, and the remaining 41 communities and Aboriginal communities were to allocate 40% of their funding to HF programs.
We discuss the theoretical and practical implications of what we learned about how evidence makes its way into policy and the implications of these findings for the expansion/extension of HF in Europe and internationally.