Anaemia is one of the most frequent co-morbidities in patients with heart failure. Its prevalence increases from 4% to7% in subjects with asymptomatic left ventricular dysfunction to >30% in patients with severe heart failure. Renal insufficiency, activation of inflammatory mediators and treatment with renin-angiotensin antagonists seem to be its main determinants. The results of many studies agree in providing evidence that anaemia is a powerful independent determinant of survival in patients with heart failure. However, the mechanisms of this relation are still not fully understood. Moreover a favourable effect of the correction of anaemia on prognosis has not yet been shown. Also In addition to this, controlled studies assessing its effects on exercise tolerance have yielded controversial results. Further research is needed to assess the effect of correcting anaemia in chronic heart failure (CHF) patients; ongoing reduction of events with RED-HF (Darbepoetin alpha in heart failure) trial will help define the role.