In spite of improved surgical techniques and fixation devices, non-union still reportedly occurs in 10-30% of cases of femoral neck fracture. A variety of methods of treatment that preserve the femoral head have been described, yet there are few reports on the results of valgus intertrochanteric osteotomy in cases of femoral neck non-union. We treated 11 such cases with valgus intertrochanteric osteotomy performed at one centre and using a single surgical technique. The cases were evaluated clinically and radiographically at a mean of 4.9 years. All of the non-unions were shown radiographically to have healed by an average of 12.5 weeks. Functional outcome was excellent for nine patients and poor for two who underwent subsequent total hip arthroplasty for avascular necrosis of the femoral head. We conclude that valgus intertrochanteric osteotomy is an effective treatment for femoral neck non-union, but avascular necrosis of the femoral head is a possible complication.