The Nimrod MRA4 was an ambitious program intended to provide the British Royal Air Force with a high capability multi-mission aircraft with an emphasis on anti-submarine warfare/anti-surface strike/maritime patrol missions. As the focus of the volume is the Nimrod MRA4 program, only a brief resume of the design heritage going back to the first and second generation Nimrod, themselves derived from the de Havilland DH106 Comet 4, is provided. The volume draws on textual and graphic material from the respective design house/test team and governmental papers in an attempt to arrive at an objective account of the program from inception, development/testing, to cancellation, almost on the eve of service entry.