A prospective trial of immediate operation was carried out on all 123 patients aged 50 years and over who presented with acute non-variceal bleeding as shown endoscopically. The mortality rate was 11.4%. Four hundred and sixty-seven similar patients treated by a conventional and more conservative approach, viz., surgery only for massive, continuous or recurrent bleeding, over an earlier period of three years, had a mortality rate of 6.4% during the acute bleeding episode. In the latter series, the mortality for the 161 patients with emergency surgery was 11.8%. The aggressive approach carries no advantage over the conservative approach and is not to be recommended. In both series surgery for haemorrhage with associated medical illness carried a similarly high mortality (27.3% and 26.3% respectively), indicating that the timing of surgery in such patients, whether it is done as early or as late as possible, does not influence the outcome. This mortality rate of immediate Billroth gastrectomy for gastric ulcer was low (4.8%), so that operation in such patients should not be delayed.