Thor: Anatomy of a Weapon System examines, in plain English, the technical aspects of the Thor IRBM. The missile and its ground support equipment are covered in detail. The guidance system is conveniently spread across two chapters and includes a sub section to help understanding of the gyroscopes. The ground based guidance components, including the mysterious theodolites, are described with accompanying drawings. Included are discussions on ballistics and how the properties of the Earth affect the missile’s flight. A chapter is dedicated to Thor’s raison d’etre; the 1.44 megaton warhead, its principles of operation and its terrifying effects. The launch countdown process is comprehensively covered in a series of easy to follow flow diagrams, accompanied by detailed drawings and descriptions of the launch control consoles and equipment. The launch site itself is examined with details of surveys, locations and layout. Detailed drawings of site buildings, by the author, complete the book, which contains photographs from the author’s collection, believed to be previously unseen.