During the period 2010–2011, when the At Home project was conducted, a questionnaire was sent to 420 non-governmental organization (NGO) key managers in six Canadian cities to enquire about their collaboration with public services and their perspective on the services for homeless people with serious mental illness (SMI). NGOs constituted a dense network of collaboration among themselves. With regard to public services, housing and shelters were two services that NGOs had frequent contact with, followed by the healthcare addiction sectors and, to a lesser extent, social service and the justice sectors. Education and employment were both located in the network periphery. In general, NGOs viewed housing availability and accessibility to health services as largely unsatisfactory. They called for better public support, coordination, and funding.