Among the general heart failure (HF) population, over half have diastolic HF (DHF). The proportion of DHF increases with age, from 46% in patients younger than 45 years to 59% in patients older than 85 years. The diagnosis of DHF is made by the combination of signs and symptoms of HF with preserved systolic function (left ventricular ejection fraction >50%), and evidence of diastolic dysfunction obtained by echocardiographic Doppler examination, invasive hemodynamic evaluation, or an elevation of serum B-type natriuretic peptide. The most common risk factors for the development of diastolic dysfunction and DHF include long-standing hypertension, older age, female sex, obesity, diabetes, chronic kidney disease, and coronary artery disease. Acute decompensation occurs in the setting of pressure overload, volume overload, or superimposed cardiac ischemia. The cornerstones of in-hospital management include blood pressure and volume control, heart rate control, and correction of precipitating factors. Priorities in the outpatient clinic include optimal blood pressure control, maintenance of euvolemia with minimal or no diuretics, and, potentially, use of disease-modifying drugs including angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, aldosterone receptor blockers, beta-blockers, and digoxin. Long-term regression of left ventricular hypertrophy, improvement in diastolic filling parameters, and sustained reductions in B-type natriuretic peptide may be future treatment targets for this condition.