Post-traumatic stress disorder (PTSD) is a condition that appears to be becoming increasingly prevalent in psychiatric and general practice. Davidson (1992) reports a lifetime prevalence of 1–9% in the community, with high levels of chroniciry and comorbidity. It routinely features in the general as well as medical literature following major traumas such as the Herald of free enterprise disaster. PTSD is also growing more important in medicolegal terms, as the recent police attempt to obtain compensation for their experiences in the Hillsborough tragedy demonstrates. Despite the high profile of the condition and the repeated descriptions of its development and (partial) resolution after every major disaster, there is very little research into the most effective means of preventing or treating PTSD. The usual approach of debriefing has been shown to be without effect (Deahl et al, 1994) and a recent review of drug treatments revealed only a few small-scale studies, none of which would be suitable tor [he licensing of a drug for this disorder (Davidson, 1992). This may be because most drug treatments are initiated well after the trauma, which may be too late to prevent the laying down of immutable brain traces for the memories, behaviours and affect that trauma causes and which develop into PTSD.