Although Doppler echocardiography plays an important role in evaluating patients with suspected valvular heart disease, it should not replace a careful history, a meticulous physical examination, an electrocardiogram, and well-performed posteroanterior and lateral chest x-rays. Two-dimensional echocardiography can reliably evaluate anatomic valvular lesions, estimate left and right ventricular function, and exclude associated pericardial disease. Doppler echocardiography provides accurate hemodynamic parameters of the severity of aortic and mitral stenosis and the degree of pulmonary hypertension. In addition, color-flow Doppler is helpful in providing semiquantitative information with regard to the degree of MR, AR, or TR. Doppler echocardiography is very useful in evaluating patients before and after valvuloplasty but may be inaccurate when compared with cardiac catheterization immediately following mitral balloon valvuloplasty. However, in the long-term followup, after valvuloplasty, Doppler echocardiography is ideally suited to predict restenosis. A properly performed echo-Doppler study may allow the clinician to send a young patient for surgery when warranted by the clinical symptoms. However, in older patients, especially those with suspected coronary artery disease, and in multivalvular disease, cardiac catheterization may still be required.