BACKGROUND Mitral valve repair in the pediatric population remains demanding because of a diversity of apparatus anomalies and the young age of the patients. METHODS We reviewed our clinical results for mitral valve repairs for congenital mitral insufficiency. Forty-nine consecutive patients aged 2 months to 34 years (mean, 4.4 years) had mitral valve repair between June 1984 and December 1996. Forty-one patients (83.7%) had associated cardiac anomalies. The predominant pathologies for the regurgitations were chordal anomalies in 34 patients (69%), annular dilatation in 8 (16%), and leaflet anomalies in 7 (14%). Mitral valve repair included commissure plication annuloplasty in 43 patients (88%), modified DeVega in 11, cleft closure in 5, plication of the anterior leaflet in 3, triangular resection of the anterior leaflet in 2, chordal shortening in 1, and placement of artificial chordae in 1. Several combined techniques were required in 19 patients. RESULTS There were no early or late deaths. The follow-up period was from 6 to 166 months (mean, 88.4 months). Forty-seven patients (95.9%) were in New York Heart Association class I. The long-term echocardiographic studies showed that 2 of 30 patients without reoperation had moderate regurgitation. The actuarial freedom from reoperation was 85.6% (95% confidence limits, 72.8%, 98.4%) at 13 years. Five patients (10.2%) required valve replacement from 13 days to 75 months after the valve repair. Two patients had cerebral ischemic events as a result of cardiomegaly and atrial fibrillation. CONCLUSIONS Valve repair for congenital mitral insufficiency gave adequate results in combination with commissure plication annuloplasty and other techniques with excellent long-term functional status.