The housing first (HF) model for individuals experiencing homelessness and mental illness differs by design from traditional models that require consumers to achieve “housing readiness” by meeting program or treatment prerequisites in transitional housing settings prior to permanent housing placement. Given a growing body of evidence for its favorable outcomes and cost effectiveness, HF is increasingly seen as an alternative to and argument against these traditional programs. As such, it is important that the elements and implementation challenges of the HF model be clearly understood and articulated. This qualitative study explored a largely unexamined aspect of the HF model—the need for and meaning of temporary residential settings (interim housing), a place to stay while waiting to secure permanent housing—using interviews and focus groups with service providers and consumers who experienced interim housing during implementation of HF in a large urban center. Although interim housing may not be necessary for all programs implementing the model, our study revealed numerous reasons and demands for safe, flexible interim housing options, and illustrated how they influence the effectiveness of consumer recovery, continuous service engagement, and housing stability. (PsycINFO Database Record (c) 2014 APA, all rights reserved)