Heart failure with preserved ejection fraction (HFpEF) is a complex clinical syndrome based on traditional heart failure symptoms with documentation of increased left ventricular filling pressures and preserved left ventricular ejection fraction. The exact mechanisms that induce HFpEF are not known. End-diastolic ventricular stiffness does not seem to be acting alone. Substantial mortality exists compared with healthy age-matched controls, as well as significant health care expenditures on hospitalizations and readmissions. This article reviews the epidemiology, pathophysiology, and treatment of heart failure with preserved ejection fraction (HFpEF). Current practice guidelines focus on remedying volume overload, aggressively controlling hypertension, and treatment of comorbid conditions that contribute to decompensation.