As a result of inadequate housing and income, people experiencing homelessness face multiple health challenges, including poor health outcomes and lack of access to health care services (Frankish, Hwang, & Quantz, 2005; Hwang et al., 2011; Hwang et al., 2010). As a consequence of their living situations, people experiencing homelessness are more vulnerable to transmission of disease, especially during public health crises such as pandemics (O’Sullivan & Bourgoin, 2010). For example, they may not have access to clean water for hand washing, or may be forced to sleep in overcrowded spaces. Since 2000, there have been several public health emergencies that have compromised the health and wellbeing of many communities, raising legal, political and ethical concerns (Gostin & Berkman, 2007; Wilson, 2006). In this case study, we look at the response in Victoria, British Columbia (BC) to the 2009 H1N1 crisis, with a focus on lessons learned for cross-sector collaboration in addressing public health emergencies in the context of homelessness. We begin by describing homelessness in Victoria, and the policy context for addressing public health emergencies in the city and province. Then, drawing on data collected from policy-makers, service providers and those experiencing homelessness, we describe that city’s response to the H1N1 threat, including pandemic planning, communication of H1N1 information, prevention efforts (including the delivery and uptake of vaccinations), and potential and actual impacts on health and social services provision.