A retrospective study of a long stay population from 1952-58 shows the patients chosen for tranquillizers in the long stay group are those with the best outlook as far as discharge is concerned. Nevertheless, tranquillized long stay patients when compared with non-tranquillized patients do nothave a better prospect of discharge and may indeed to some extent have a lesser prospect. Hospitaltreatment with tranquillizers does not alter the chance of re-admission of discharged long stay patients. Ward behaviour, apart from some aspects of "disturbance," is little influenced by tranquilizers which are themselves possibly associated with the introduction of new symptoms. Disturbed wards invite treatment and on them, as on other wards, tranquillizers have replaced other sedatives, with the numbers of patients ultimately treated exceeding the numbers previously sedated.