Many patients with heart failure (HF) have a normal left ventricular ejection fraction, and are labelled as having HF with preserved left ventricular ejection fraction (HFPEF). Hypertension, atrial fibrillation and age are important contributors to the development of HFPEF and, therefore, its prevalence is likely to increase in the next few decades. The pathophysiology of HFPEF is heterogeneous but with a final common pathway leading to congestion. HF remains a clinical diagnosis but the plasma concentration of B-type natriuretic peptide (eg BNP/N-terminal prohormone BNP (NT-proBNP)), a marker of congestion, is an essential component. Imaging, usually by echocardiography, is required to determine the cardiac phenotype (ie valve disease, left ventricular ejection fraction) underlying HF. A superficially normal echocardiogram does not exclude a diagnosis of HF. No treatment has been shown conclusively to alter the prognosis of HFPEF. However, treatments directed at congestion and hypertension, such as diuretics, mineralocorticoid receptor antagonists (MRAs) and angiotensin converting-enzyme inhibitors, may improve symptoms and probably do improve outcomes. No treatment has yet been shown to reverse the underlying myocardial pathology of HFPEF, although there is some hope that MRAs might.