Strongyloides hyperinfection syndrome is a rare but serious and often fatal complication of strongyloidiasis, usually precipitated by immune suppression (frequently caused by corticosteroidal drugs). Infections with Strongyloides stercoralis are known to occur in British veterans who served in South-east Asia during the Second World War, particularly in those held as prisoners of war by the Japanese. No information on the frequency of disseminated strongyloidiasis in these men is, however, available. A multi-source enquiry designed to detect the cases of Strongyloides hyperinfection syndrome that occurred, in the U.K., in the 60 years following the end of the Second World War was therefore initiated. The relevant data were collected from death certificates, searches of the medical literature, enquiries with veterans' organizations, and questionnaires sent to all the units of infectious and tropical disease in the U.K.. Overall, 25 cases of hyperinfection in the U.K. were detected but only two involved veterans of the Second World War (one British ex-Far East prisoner of war and a British former soldier who had been involved with the evacuation of Singapore in 1945). Although the risk of hyperinfection in veterans appears small, information from the literature and veterans' organizations indicates that there are still probably 300-400 such veterans who remain alive in Britain and have Strongyloides infections. Attempts at the detection and eradication of the infections in the surviving veterans are recommended.