Updated 2022 version of the register  

The book is 333 pages with over 75 pictures (including some in colour) and 18 coloured maps. 

This volume covers the Great Western Railway area as it was between 1923 and 1947. It includes, therefore, all the Great Western signalboxes and those of the various constituent companies. Geographically, the area extends to mid Wales, Cheshire, West Midlands, and Weymouth as well as Paddington to Penzance.

This volume includes all known Great Western signal boxes, based on the extent of the G.W.R. as at 1947 but excludes Chester to Birkenhead which will be covered in the LNWR register. It also excludes lines later transferred to B.R.(W.R.) such as Gloucester-Bristol (see Midland register) and ex-LMS lines in South Wales (see Midland or LNWR register).

The first edition was published in 2007 and a second edition followed in 2011.