This retrospective study evaluated the results of permanent hemiepiphyseodesis for the correction of non-Blount's coronal plane angular knee deformity. The medical records and radiographs of 75 patients with 125 angular knee deformities were analyzed for overall rate of success and factors predicting successful correction of deformity. There were 38 patients with idiopathic genu valgum and 37 with various other skeletal disorders. Sixty-nine out of 75 patients had reached skeletal maturity at latest follow-up. One hundred six knees out of 125 were successfully treated by the procedure. Of the 19 remaining knees, 15 were operated on too close to skeletal maturity to expect correction and 4 were technically unsuccessful in achieving closure of the targeted physis. There were no complications other than overcorrection, which occurred in 15 knees (11 patients). This study indicates that permanent hemiepiphyseodesis is a very useful procedure if performed in a timely and technically successful manner.