Left ventricular diastolic dysfunction (DD) is recognized as an important contributor to diastolic heart failure and is associated with increased morbidity and mortality. The evaluation of diastolic function has become an integral part of a full echocardiographic study and is recommended by the current guidelines of the American Society of Echocardiography and the European Association of Cardiovascular Imaging. Recent data show that diastolic function is not static, but rather a dynamic phenomenon; worsening of diastolic function is associated with worse outcomes, whereas its improvement is associated with better survival. The purpose of this article is to review the echocardiographic assessment of diastolic function with an integrative clinical practical approach, discuss plausible mechanistic links between DD and clinical outcomes, summarize the prognostic value of left ventricular and right ventricular DD in various patient cohorts, the strengths and limitations of the data, and finally, give insight into future directions.