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.

The brand London Transport came into being in 1933 and remained until 2000. Prior to 1933, the transport system in London was owned and managed by several independent and separate organisations. The Underground railways were developed and owned by the Underground Electric Railways Company of London (est. 1902) and the Metropolitan Railway (est. 1863) whilst the Tram and Trolleybus networks were under the control of various local authorities and public companies. The London County Council operated tram routes within the County of London but its responsibility did not extend to the bus or tram routes that ran outside its area and it did not hold responsibility for the railways which also extended into neighbouring counties. From 1933, the London Passenger Transport Board (LPTB) was established in accordance with the 1933 London Passenger Transport Act and covered both the County of London and adjacent counties within a 48-km radius. For the first time services within the London area were amalgamated. A significant proportion of tram routes were brought under the responsibility of the LPTB, as were the Underground Electric Railways Company of London lines and the bus services; this became known as the London Passenger Transport Area. It was then that the familiar ‘roundel symbol’ (designed in 1918) and the tube map designed in 1931 were adopted by the LPTB. The second World War was to cause some disruption to the ongoing programme, resulting in delays and also the abandonment of some projects. During the post war years, the transport authority was the London Transport Executive until 1962. It was taken into public ownership and London Transport and British Railways were under the same jurisdiction for the first and only time. It was during this time that recruitment began directly from the Caribbean and work began on resolving war damage to stock and stations as well as the completion of projects previously delayed during the war. The post-war years also saw some major developments within London transport, including the withdrawal of both trams and trolleybuses and the introduction of the iconic AEC Routemaster bus in 1956. From 1963, the transport authority was the London Transport Board until 1969 and it reported directly to the Ministry of Transport and no longer held direct association with the management of British Railways. Public transport was not heavily invested in during this period and motor cars increased in popularity. Unprofitable railways across Britain were also closed. The 1960s also witnessed the opening of the underground Victoria line and also the introduction of the single-deck bus. From 1970, the Greater London Council was the transport authority and remained so until 1984. Control of green-coloured country buses and Green Line Coaches were passed on to London Country Bus Services which became part of the National Bus Company. As with many organisations during this period, London transport suffered a severe lack of funding from central government as well as major staff shortages. The inter-modal zonal ticketing system was also introduced in 1981. From 1984-2000 London Regional Transport was the transport authority and was also under direct state control, reporting to the Secretary of State for Transport. Under the London Regional Transport Act in the 1980s subsidiary companies were established to run Underground and bus services. This period also saw the inclusion of British Rail services into fare options and the opening of the Docklands Light Railway in 1987. From 2000 to the present day, the transport authority has been Transport for London (TfL). Unlike its predecessors, it has never been commonly known as London Transport and holds responsibility for many other transportation functions such as road management, taxi and private hire licensing and also cycling and walking. Responsibility for the Underground was not given until 2003. TfL have been the longest running transportation organisation in London to date.