Despite decades of research, youth suicide remains difficult to understand and predict, and thus challenging to prevent. Drawing on the well-established literature on major industrial accident prevention – another notoriously difficult catastrophe to predict – and new data from an ethnography of suicide prevention in 4 schools in Colorado, we advance a new approach to understanding why youth suicide clusters form and persist. This approach recognizes the school as a formal organization facing competing demands, goals, and constituencies, all of which can compromise the school’s ability to prevent suicide. We conclude (1) by setting a new agenda for research on suicide prevention in schools and (2) by offering new strategies to build effective school-based mental health safety systems.