Given the high incidence of depression, it is necessary and desirable that as many cases as possible should be treated by general practitioners. However, general practitioners are on the whole ill-prepared to meet the needs of depressed patients. In the last few years a big effort has been made in certain countries to improve the psychiatric training of general practitioner and to enable him the better to detect and treat depression. Communication between psychiatrists and general practitioners is made difficult by the lack of a common language and terms used should be defined clearly. Some of the problems in practice are diagnostic in nature: detect of the depressive syndrome, of the minor or masked forms; differential diagnosis of depression and anxiety. The commonest problems in treatment are: selection of drug, monitoring of side-effects, duration of treatment. The general practitioner needs information also on such questions as: how to evaluate the risk of suicide; when to call in the specialist; how far to use supportive psychotherapy. Some types of depression are particularly likely to come to the general practitioner: depression masked by physical symptoms, depression associated with or secondary to physical disease, depression in the elderly.