The consequences of terrorism, wars and natural disasters are a challenge to the psychiatric profession. The large numbers of people estimated to have mental health problems surpass the capacities of existing mental health services, whether modern or traditional. The bulk of the 35 million refugees and internally displaced people worldwide reside in countries that, on average, have less than one psychiatrist or psychologist per 100 000 people (WHO, 2001). Even the 500 000 people estimated to need some form of psychological support after the attack in New York on 11 September 2001 exceeded the service capacity, despite the fact that New York has the highest density of mental health professionals in the world (Herman & Susser, this issue, pp. 2–4). Elsewhere, many survivors of various types of disaster reside in peripheral areas of countries and are not covered by modern mental health services.