Since its introduction into clinical practice ten years ago, percutaneous mitral balloon valvotomy has developed into a well accepted procedure for patients with tight mitral stenosis. The different techniques with their pros and cons are discussed. The indications for mitral balloon valvotomy are based on a solid clinical and echocardiographic examination. The procedure itself requires technical skill and experience. After the procedure there is often a dramatic decrease of symptoms by an almost doubled mitral valve area to values of 1.8 to 2.0 cm2. The rate of complications is acceptable and compares well with surgical valvotomy. The most feared complications are pericardial tamponade (1%) and the development of severe mitral regurgitation in 10%. Percutaneous mitral balloon valvotomy is therefore a first choice therapy for well selected patients with tight, pliable mitral stenosis.