Gooderson addresses the fundamental questions of whether the employment of air resources in the close support role provided sufficient advantage at the battlefront to justify the expenditure of effort and the risk to aircraft and pilots, and whether air support proved to be of more value - and more cost effective - when directed upon interdiction targets behind the lines, such as German communications, transport and supplies. The principal sources consulted were contemporary Army and Air Force formation and unit records and reports, and contemporary Allied Operational Research material. The book examines the nature of Operational Research in the period, the joint Air Force/Army systems established by both the British and Americans for providing and controlling air support, the characteristics of fighter-bomber aircraft and the organisation and tactics of fighter-bomber units. This precedes an analysis of close air support for mobile and airborne operations, the employment of fighter-bombers against German armoured forces, the use of heavy and medium bombers in the close support role, the comparative effectiveness of fighter-bombers and ground artillery and the effective of fighter-bombers in the interdiction role.