The AIC has operated the National Deaths in Custody Program since 1991, following a recommendation by the Royal Commission into Aboriginal Deaths in Custody. This study updates and extends an earlier AIC study, which examined the important issue of self-inflicted deaths in prison custody using deaths in custody data for the period 1999–2013. Regrettably, suicide remains a common cause of death in prison; however, it is no longer the most common cause of death. While self-inflicted deaths constituted half of all prison deaths between 1980 and 1998, they have declined to the point that between 2004 and 2013—the most recent decade for which data are available—they represented around a quarter of prison deaths. This decrease reflects the considerable progress made by corrective services administrators in developing policies and practices, and implementing cell designs, that address suicide risk factors. Nonetheless, these data and coronial findings suggest there is still room for improvement, particularly in responding to prisoners with psychiatric needs and in the management of unsentenced prisoners.