Summary. Approximately half of the patients with overt congestive heart failure (CHF) have diastolic dysfunction without reduced ejection fraction (LVEF>50%). Diastolic dysfunction is an abnormality in left ventricular myocardial relaxation and/or compliance that alters the ease with which blood is accepted into the left ventricle during diastole. Elevated pressures in the left atrium are compensatory, ensuring adequate filling. All patients with systolic dysfunction have concomitant diastolic dysfunction. Indeed, in patients with CHF and reduced systolic function the level of diastolic dysfunction influ- ences the severity of symptoms. It is now clear that hypertension, coronary artery disease and other diseases and conditions commonly produce diastolic dysfunction in the absence of significant systolic dysfunction. Accurate noninvasive Dopp- ler-echocardiographic assessment of the presence and severity of diastolic impairment is crucial to the broad application and understanding of this common condition. This review discusses the clinical impact of classic and recent echocardiographic contributions to the field of diastology.