Book excerpt: The volume is an overview of the basics of biomechanics of circular external fixation. It is based on a system of coordinates that allows safer insertion of K-wires and half pins into the bone. It includes a new classification of this device, a collection of terminology, and a description of relevant equipment. It also presents the protocol of external fixation including how to avoid mistakes, and provides a numerical codified system for the application of transosseous wires.