Up to 80% of people encounter severe adverse events in their lives (De Vries & Olff, 2009). Most people will be resilient or quickly recover from negative symptoms, but a significant proportion will develop posttraumatic stress disorder (PTSD) leading to a lifetime prevalence of PTSD in about 7% (De Vries & Olff, 2009; Kessler et al., 2005). These events precipitate not only PTSD but also major depression, anxiety disorders, addiction, physical health problems, and other trauma-related disorders.