This research report presents important findings from the first four waves of the JH study, which were conducted over an 18-month period between September 2011 and May 2013. The report is structured into eight chapters, five of which explore, in depth, a key issue affecting the homeless and people facing housing insecurity. The five issues examined are: the duration of homelessness, mental illness, psychological distress, substance use, and links with and between child and adult abuse and violence.