Mitral stenosis in the younger age groups in India is a unique condition characterized by a short duration and a rapid progression of symptoms. The majority of patients with this lesion develop pulmonary hypertension at an accelerated pace, and about one third have associated congestive failure and functional tricuspid regurgitation. Five hundred consecutive patients with this condition were treated surgically, 493 with a closed valvotomy. The over-all hospital mortality rate of 5.8 per cent was related to the severity of the preoperative functional status. In the last 150 cases, the figure dropped to 2 per cent. Assessment during the first 5 years after surgery revealed an excellent functional status in 85 per cent. The incidence of restenosis was only 3.4 per cent in the first 5 year period and 11 per cent in a subsequent 6 to 10 year follow-up period. Twenty of the 21 subjects with restenosis had an excellent functional result following closed transventricular valvotomy, and this status has been maintained during the follow-up period. To our knowledge, there are no other reports of long-term follow-up data in young patients undergoing surgical treatment for mitral stenosis.