Despite diastolic dysfunction is recognized to play a major role in the pathophysiology of heart failure, the importance of an accurate diagnosis and treatment of this syndrome in clinical practice is poorly established. Recent publications suggest that diastolic dysfunction is the primary cause of heart failure in 30-50% of patients. Several studies also show that, in a significant number of patients with systolic dysfunction, diastolic function is the major determinant of their symptomatic status, their response to treatment and their outcome. Other preliminary data suggest that diastolic dysfunction is an important cause of exercise intolerance in patients with chronic hypertension. This paper discusses the most recent concepts related to the mechanisms, the diagnosis and the treatment of diastolic dysfunction based on diagnostic imaging techniques.