In patients with mitral stenosis the need for therapeutic intervention can be assessed by clinical and non-invasive data. Mitral valve replacement is indicated when marked dyspnoea on mild exertion, dyspnoea at rest or pulmonary oedema, haemoptysis, atrial fibrillation, recurrent systemic emboli or right ventricular failure occur in a patient with a mitral valve area of less than 1.5 cm2, as measured by Doppler echocardiography. This treatment will entail life-long anticoagulation in the majority of patients. Closed commissurotomy is no longer considered a valid therapeutic alternative due to its limited success rate but open commissurotomy and balloon valvotomy may be performed in patients with no significant calcification of valve cusps and no major concomitant mitral regurgitation. Preservation of the subvalvular apparatus and left ventricular geometry can be considered the most important advantages of these techniques. More severe chronic symptoms are generally required as indication for mitral valve replacement because of the additional long-term imponderabilities imposed by an implanted artificial device. Therefore, in patients with mitral stenosis different symptoms and clinical findings will eventually lead to different interventions.