The General Electric Company (GEC) merged AEI Traction Division and English Electric Traction in 1969 after acquiring both companies to create English Electric – AEI Traction Limited. The headquarters were located at Trafford Park in Manchester. This subsidiary company was renamed GEC Traction Limited in 1972.

Metropolitan-Vickers Electrical Co Ltd was the new trading name given to British Westinghouse Electric and Manufacturing Co on 8 September 1919. The predecessor company had sold its controlling share to the Metropolitan Carriage Wagon Co in 1916 in order to gain membership of the Federation of British Industries. In 1919, Vickers acquired the Metropolitan Carriage Wagon Co, along with its controlling share in British Westinghouse, prompting the change in name to Metropolitan-Vickers Electrical Co Ltd. The American owned British Westinghouse had established its English operations at Trafford Park in 1899, and Metropolitan-Vickers Electrical Co Ltd continued on the same site from 8 September 1919. The company was initially known for its electricity generators, later diversifying into the manufacture of steam turbines, switchgear, transformers, electronics and railway traction equipment. The passing of the Electricity (Supply) Act in 1926 provided a boost to the company’s post-war fortunes, with the creation of the National Grid generating demand for the company's products. In 1928, Metropolitan-Vickers Electrical Co Ltd merged with its rival British Thomson Houston Co Ltd, retaining both names for trading purposes. The following year, on 4 January 1929, Associated Electrical Industries Ltd (AEI) acquired Metropolitan-Vickers Electrical Co Ltd and the British Thomson Houston Co Ltd. Again, both trading names were retained, and a fierce rivalry was established between the firms which the parent company was unable to control. In 1931, Sir Felix Pole joined Metropolitan-Vickers Electrical Co Ltd as its new chairman. He oversaw a period of expansion for the company leading into the Second World War. In 1939, seeking a more concise name for the company, the Board of Directors decided upon Metrovicks, which became interchangeable with the official company name of Metropolitan-Vickers Electrical Co Ltd. Under Sir Felix Pole's chairmanship, Metropolitan-Vickers developed new products for the aviation industry and during the war was one of the sites where Lancaster bombers were built. In 1941, the company developed the first British axial-flow jet engine, the Metrovick F.2. Following the Second World War, the company appointed Oliver Lyttelton as chairman, with the aim of increasing the efficiency and productivity of AEI. Despite his success in achieving this aim, Lyttelton was unable to resolve the commercial rivalry between Metropolitan-Vickers Electrical Co Ltd and the British Thomson Houston Co Ltd. During his second period as chairman, from 1954-1963, Lyttelton, now Lord Chandos, oversaw the development by Metropolitan-Vickers Electrical Co Ltd of the first commercial transistor computer, the Metrovick 950. Chandos also resolved to extinguish the competition and internal divisions between Metropolitan-Vickers Electrical Co Ltd and the British Thomson Houston Co Ltd, and both company names ceased to be used from 1 January 1960, with all subsidiaries going on to trade under the name of Associated Electrical Industries Ltd.

In 1929 Vickers Ltd and Cammell Laird merged their rolling stock activities in a new company, the Metropolitan-Cammell Carriage, Wagon and Finance Company Ltd with Vickers and Cammell Laird each holding 50% of the shares of the new company. Following the Second World War, the company manufactured carriages for the railways of the world, including UK, USA, Canada, South Africa, Hong Kong, Singapore, Brazil, Jamaica, and Egypt. In addition, the company manufactured mineral wagons, diesel multiple units and locomotives. However, over this period of sustained high output, international industrial development together with reductions in home market demand as orders were fulfilled, led to the necessity to reduce capacity and in 1962 the Saltley Works were closed and eventually the whole enterprise was concentrated at the Midland Works offices at Leigh Road, Washwood Heath. In the 1970s Metro-Cammell specialised in the design and construction of rapid transit vehicles for customers such as London Underground, Tyne and Wear Metro, Hong Kong Mass Transit Corporation and the Kowloon Canton Railway Corporation. They also built Maglev vehicles for Birmingham Airport, diesel multiple units for BR and Mk IV coaches for BR. In May 1989 the Laird Group sold their transportation interests to GEC Alsthom and Metro-Cammell became part of the new Anglo-French Power Generation and Transportation Group. This led to involvement in the construction of the Eurostar trains for the Channel Tunnel project. The name Metro Cammell disappeared forever in 1998 when the owners floated the company under the name Alstom.