The medical histories of 84 children who had been diagnosed as having conversion disorder were reviewed in a follow-up study, and the validity of this diagnosis was examined. The female:male ratio was 2.1:1, although below the age of 10 the ratio was almost equal. The medical histories of 62 per cent of the patients showed an organic illness, and 51 per cent had various slight to moderate EEG disturbances. The validity of the diagnosis was very high: only five were found to have organic disease during the follow-up period. Children with symptoms of conversion disorder should receive appropriate medical investigations, but the authors question whether extensive investigations could not be replaced by screening tests, combined with early psychiatric intervention.