During the immediate period before World War Two the RAF modified its command structure to rationalise for rapid expansion. Bomber Command was divided into six operational groups each flying the same type of aircraft including Wellingtons Sterlings & Lancasters. Chris Ward presents us here with the history of 4 Group Bomber Command having previously acquainted us with the histories of 3 5 & 6 Group Bomber Commands in three highly acclaimed volumes published by Pen & Sword. He continues with characteristic ease quality of research & narrative pace to present us with an operational record of the groups activities during a particularly dramatic period of aviation history. The book contains individual squadron statistics their commanding officers stations & aircraft losses. It provides a detailed reference for one of the RAFs most important operational groups.