Understanding Systems Change in Early Implementation of Housing First in Canadian Communities: An Examination of Facilitators/Barriers, Training/Technical Assistance, and Points of Leverage.

We present interim findings of a cross-site case study of an initiative to expand Housing First (HF) in Canada through training and technical assistance (TTA). HF is an evidence-based practice designed to end chronic homelessness for consumers of mental health services. We draw upon concepts from implementation science and systems change theory to examine how early implementation occurs within a system. Case studies examining HF early implementation were conducted in six Canadian communities receiving HF TTA. The primary data are field notes gathered over 1.5 years and evaluations from site-specific training events (k = 5, n = 302) and regional network training events (k = 4, n = 276). We report findings related to: (a) the facilitators of and barriers to early implementation, (b) the influence of TTA on early implementation, and (c) the "levers" used to facilitate broader systems change. Systems change theory enabled us to understand how various "levers" created opportunities for change within the communities, including establishing system boundaries, understanding how systems components can function as causes of or solutions to a problem, and assessing and changing systems interactions. We conclude by arguing that systems theory adds value to existing implementation science frameworks and can be helpful in future research on the implementation of evidence-based practices such as HF which is a complex community intervention. Implications for community psychology are discussed.