Hugh Longworth is well known for his detailed research and encyclopaedic data books on BR locomotive stock. He has published two highly successful books on DMUs and BR Mark 1 and 2 Coaching Stock and this new title follows the format of these two previous volumes to show data on all the mainline EMUs built up to 1975, including all the units that were built earlier by the individual companies before nationalisation under BR. The book covers all units built that have finished their service life and concludes with the Class 312 units, older units and coaches rebuilt (including all the Gatwick express units) and the PEP prototype sets. The data gives the same information on each class, covering performance, dimensions, capacity, number series etc. Each type is covered in detail with information about construction, technical specifications, entry into service, withdrawal and final fate. Additional sections describe unit formations. The book also gives individual individual histories of each vehicle including an indication of depot allocations during their period of service. The information will be accompanied by line drawings of each class as well as a representative selection of photographs showing the great variety of EMUs constructed from the end of the 19th century to 1975.