Prescriptions for psychotropic drugs for in-patients in the Dundee Psychiatric Service were studied for three five-month periods in 1991, 1992 and 1993 using computer data and drug sheets. Information about Journal advertising and advice to doctors was obtained for the same period. A possible effect of Journal advertising was detected in the first year but there was no further Increase in the second year in the total of prescriptions. Information is presented of a similar survey in 1975 and 1976. A high proportion of prescriptions was for formulary drugs and doctors rated the British National Formulary as the strongest influence on their prescribing.