From January 1968 through June 1970, 106 consecutive patients in the age range from twelve to twenty years had surgical treatment of their idiopathic scoliosis under the same management regimen. This consisted of careful articular-process fusion, usually in a preoperative cast, combined with Harrington instrumentation and addition of autogenous iliac-crest bone graft; careful application of a modified Risser-Cotrel cast and ambulation on an average of ten days following surgery; cast change at four to five months, and then removal of all support at an average of nine months following surgery. Follow-up averaged nineteen months. Correction obtained on the day of surgery compared with final correction standing out of plaster revealed an average loss of only 5 degrees. The pseudarthrosis rate was 4.7 per cent.