Carvedilol is the first beta-blocker to obtain approval for treatment of heart failure. Improvement in hemodynamic parameters was initially documented in three methodologically sound studies involving 156 patients. Follow up was limited to 16 weeks. A placebo-controlled, double-blind trial involving 1094 patients showed beneficial effects on overall mortality of 4.6% in absolute terms after a median follow up of 6.5 months. This benefit was not found in another trial involving 415 patients followed on average for 19 months. Results for symptom-based criteria conflict. When treatment is introduced very gradually, adverse effects (malaise) seem to be minor and infrequent. Carvedilol's place in the treatment of heart failure is not yet precisely documented.