The authors discuss free microvascular bone transfers in general, and propose a new classification for idiopathic femoral head necrosis. They then present a technique they have been using for 11 years, with the goals of providing both mechanical support and an improved blood supply to the femoral head. This technique involves clearing the necrotic area of the femoral head, filling the area with cancellous bone taken from the greater and lesser trochanters, and transferring a fibular microvascular graft. The approach is transtrochanteric and spares the capsule. Vascular anastomosis is done with the lateral branches of the deep femoral artery, sparing the anterior circumflex artery which is important to the blood supply of the femoral head. Forty-five cases have been surgically managed over 11 years. Eighteen cases with follow-up longer than five years were analyzed, providing an 84 percent successful outcome with both very good and good results.