Familicide-suicide following separation is under-researched and remains a poorly understood phenomenon. Findings from previous research are inconclusive in relation to both risk factors and perpetrator motivation. This article explores the relevance of long-term biopsychosocial antecedents in cases of familicide-suicide that occurred in Western Australia between 1986 and 2005. A conceptualization of the hypothesized risk factors in familicide-suicide is proposed based on attachment theory, personality dysfunction, the neurobiology of trauma and the possible unconscious motivation of perpetrators, which may prove helpful in assessing the risk of familicide-suicide in family court cases. The research identified and articulated a number of warning signs to familicide-suicide that are often not identified, or appreciated, by decisionmakers. Suggestions are offered for changes to practice that may be helpful in identifying and responding to high-risk cases in a way that enhances safety. Abstract published by arrangement with John Wiley & Sons.