Examination of occupational health records for National Health Service employees in hospitals in England and Wales for 1980-84 has shown that the incidence of pulmonary tuberculosis has fallen for all occupations. Levels for all occupational groups, except mortuary attendants, are now comparable to or lower than that for the general population. An average of 3 cases of pulmonary tuberculosis would be expected to occur annually amongst the 20,790 staff (including mortuary attendants) classified as being at higher risk and offered annual X-rays. Routine annual X-rays failed to identify 60 per cent of the cases found within this group in this study, the diagnosis being made after individuals presented with clinical symptoms. The falling incidence and low yield from chest X-rays found in this study suggest that the current policy of annual chest X-rays for NHS staff in the higher risk category no longer seems justified.