Heart failure with preserved systolic function, or diastolic heart failure, represents the neglected other half of the pandemic of heart failure. Unlike previously held beliefs, diastolic heart failure carries with it the same connotation of morbidity and mortality as systolic heart failure, particularly in the elderly. Due to lack of standards in application of the diagnosis of diastolic heart failure, studies are difficult to interpret due to heterogeneity in the clinical criteria applied to the patient enrollment. It is imperative that preventive efforts be implemented in high-risk groups, and screening measures with newer biomarkers be considered for identifying underlying structural heart disease in order to employ preventive therapy early in the course of illness. No evidence-based therapeutic strategy to reduce morbidity and mortality has been established, even after the diagnosis of diastolic heart failure is manifest. Current therapy targets lusitropic abnormalities in the realm of impaired relaxation, abnormal diastolic compliance, avoidance of tachycardia, and restoration of atrial booster pump function. Outcomes-based placebo-controlled clinical trials are currently underway to define appropriate therapeutic strategies in diastolic heart failure.