A description of a structured psychiatric interview the Present State Examination is given (P.S.E. Wing 1967). We replicated Kendell's reliability study of the 8th version of the P.S.E. Our aim was to test the applicability of the scale when used by raters without formal training in scoring the P.S.E. and working under normal clinical circumstances. The results were somewhat disappointing, agreement amongst our raters being markedly lower than in Kendell's study. Three possible causes for our relative lack of interrateragreement are mentioned: insufficient training of the raters, failure to eliminate a systematic bias of some raters and the severe pathology of our patient population.