A multi-centre controlled trial of amitriptyline, dothiepin and mianserin in the treatment of depressive illness was undertaken in psychiatric inpatients over the age of 65. Despite the co-operation of many of the leading practitioners in this field in Great Britain, it proved impossible to recruit sufficient patients for firm conclusions to be drawn. Forty-five patients were entered into the trial, 13 withdrew because of lack of improvement, 4 because of intercurrent physical illness, 3 because of adverse effects of trial medication and 2 because of lack of compliance. Only 11 of the 23 patients completing had a final score on the Hamilton Depression Rating Scale of 10 or less. No treatment showed a significant superiority over the others, nor was there any difference in tolerance.