This technique was devised in Pamplona more than 20 years ago in 1984. However it took a long time for anything to be actually published (J Bone Joint Surg, 1994) because none believed it was really possible to preserve the joint of the patient. As time has gone on, the technique has aroused an outstanding amount of interest among doctors dealing with bone tumors. Nowadays there are people starting to employ the technique in several countries, and there are many doctors wanting to learn about it. With considerable experience now in the application of this technique, and great interest from many professionals from all over the world, the time is right for a comprehensive rundown of these ideas which will help many children who would otherwise almost certainly be amputated.