From two large scale studies in patients with suspected acute myocardial infarction we report the outcome in diabetics after treatment with either metoprolol or placebo. In the Göteborg Metoprolol Trial mortality at 3 months was reduced by metoprolol from 17.9% to 7.5% and late infarction was reduced from 16.4% to 3.8%. In the MIAMI Trial, mortality was decreased by metoprolol from 11.3% to 5.7% and the occurrence of late infarction was decreased from 4.5% to 3.1% during 15-day follow-up. Compared with the overall results, the effect of metoprolol on mortality appears particularly impressive in diabetics.