Severe posterior annular calcification poses a particular challenge to mitral valve repair. In a series of 252 mitral valve repairs for myxomatous degeneration performed between 1980 and 1993, 14 patients had a severely calcified posterior mitral valve annulus. Ages ranged from 61 to 81 years. Twelve patients were preoperative NYHA Class III or IV, and five patients required concurrent coronary artery bypass procedures. Operative techniques included complete resection of the calcified posterior annulus, resections of portions of the posterior leaflet with leaflet advancement, and placement of an annuloplasty ring. There were no operative deaths and all patients had a postoperative echocardiographic confirmation of relief from mitral regurgitation. During a mean follow-up time of 36 months (6 months to 8 years), there has been one late valve reoperation and only one late death, from thromboembolism in a patient with atrial fibrillation. These data indicate that even in the presence of severe calcification of the posterior mitral annulus, mitral valve repair for myxomatous degeneration can be performed with a low-operative risk and satisfactory long-term results.