On average, a disaster occurs somewhere in the world every day (Norris et al. 2006), and there is widespread agreement that disasters can influence the mental health of the affected population (Difede and Cukor 2009). Disaster mental health research is typically concerned with (1) uncovering the mental health effects of disasters, and (2) investigating the effectiveness of interventions for survivors. ‘Understanding the psychological consequences of natural and technological disasters and terrorism – and measuring the effectiveness of postdisaster interventions – are critical tasks for contemporary researchers and practitioners’ (Norris et al. 2006: cover).