The average number of reported disasters worldwide, based on International Federation of the Red Cross criteria, increased from an average of 428 per year between 1994 and 1998 to 707 per year between 1999 and 2003.1 Although definitions of disasters vary, most definitions concur that disasters may be attributed to natural, technological, or human causes. During the past decade, several high profile disasters have sharpened the media and scientific focus on disasters. In terms of natural disasters, the horrific Southeast Asian tsunami at the end of 2004, claiming more than 200,000 lives worldwide, highlighted both the devastation that natural disasters can wreak and their unpredictability. Our increasing reliance on technology comes hand in hand with a greater risk of the possible consequences of this reliance. The dam collapse at Buffalo Creek and the threatened nuclear power plant failure at Three Mile Island were two of the sentinel events of the past decades that increased our awareness of the threat of technological disasters. With respect to human-made disasters, two unprecedented terrorist attacks, the bombing of the Murrah Federal Building in Oklahoma City in 1995 and the attacks on the World Trade Center in New York City in 2001, brought home the notion that human-made mass traumatic events are a source of concern in the United States. Two-and-a-half years after the September 11, 2001 terrorist attacks, on March 11, 2004, the Madrid train bombings were the largest single terrorist attack in Europe. In addition, other mass traumatic events continue to threaten the health of populations worldwide. There are approximately 16 wars being fought today.2 In 2004, there were 17,084,100 refugees around the world,3 ensuring that the consequences of these wars would continue for years to come.