Design work was by the London, Midland and Scottish Railway Company (LMS), who had no prior experience in the design and production of fighting vehicles. and had been invited to participate under a Government policy that British companies should develop necessary skills in expectation of war. The design assumed a welded hull rather than the usual rivetting. The turret was designed by Nuffield, with Henry Meadows designing a new low profile engine for it. On 17 April 1939, before even a single prototype was produced, the first 100 vehicles were ordered from the LMS. Additional orders soon followed, with English Electric and Leyland Motors joining the production effort, for a final production total of 1,771 Covenanters. Nuffield was also approached, but preferred to design its own offspring of the A13 line, which became the Cruiser Mk.VI Crusader.