London's transport network expanded greatly during this period as the move to the suburbs continued unabated. Life in the suburbs was now attainable for working class families due to the improved transport system and cheap workmen's tickets. By 1912 approximately 40% of suburban commuters travelling within a 6-8 mile radius of London were working class.

New suburbs were built such as Golders Green, Finchley, Edgware and Hendon, characterised by mock Tudor houses and neat gardens. The Underground companies expanded their services to match. The Metropolitan Railway went one better than most. As well as extending its services to Buckinghamshire it set up a company, in 1919, to buy land and built housing estates along its line. In the 1920s and 30s thousands of people moved to houses in 'Metroland', from Baker Street to Rickmansworth.

The Central London Railway opened in 1900, from Shepherds Bush to Bank via Oxford Street. It had a flat fare of two pence, bigger tunnels, trains and more power (so less blackouts) than the City and South London railway, who ran the first Underground company. It was so successful that the Metropolitan and District lines lost four million customers between them in just the first few months. Electrification of the lines took off in the first decade of the century at the same time the Bakerloo, Piccadilly, and Northern lines opened.

Hackney was still without a tube. A proposal in 1905 to expand the network to Walton Cross from Monument, via Shoreditch and Hackney, was passed by Parliament but failed to happen as sufficient funds were not found in time. The success of the rapidly expanding tube network posed a threat to the Great Northern Railway and prompted them to block attempts to extend the tube past Finsbury Park. They were successful until 1924, when an extension line was agreed in principle, but sadly for Hackney it was decided to turn down the option of a line from Liverpool Street to Hackney and Stoke Newington in favour of extending the Piccadilly line to Acton Town. However in 1932 the Piccadilly line was extended the other way from Finsbury Park to Cockfosters giving Hackney a tube station at last, Manor House.

The rest of Hackney made do with an extensive horse tram network. The horses' hooves were shod with iron and the trams had steel wheels. As the roads were usually macadam or granite the noise was terrible. Around schools and churches the roads were set with wooden blocks to muffle some of the noise and allow the occupants to think.

The tram network was electrified from 1904-1913. At the same time the horse buses were replaced by motor buses. The last horse bus journey was in 1914. The motor buses became very popular in 1920s but as there were no fixed stops and lots of competition bus drivers would sometimes block each other or race for passengers. To prevent these dangerous practices, and to prevent less profitable routes being ignored, all London bus companies were merged in 1933 to form London Transport, or LT as it became known.

It was also in the 1930s that London saw trolley buses on the streets. Trolley buses were short-lived. They were a cross between trams and buses. They were powered by the overhead electrics but had rubber tyres instead of running on rails. This proved to be a disadvantage as the bus network grew because trolleybuses could not go outside London into countryside of the surrounding counties such as Middlesex and Surrey. These areas were covered by motorbuses and Londoners were encouraged to take day trips on these services in poster campaigns. The largest operator was Green Line Coaches who ran distinctive green buses. During World War II the services were suspended and the buses used as ambulances, army canteens and troop carriers.

London Transport was responsible not just for the buses but also the trolleybuses, trams and Tube services. The bus services subsidised the Tube, allowing it to expand greatly in the 1930s. During this time London Transport employed over 70,000 people and was a highly regarded employer offering good wages and even a home on retirement.

The Chief Executive of London Transport was Frank Pick. Pick realised that London Transport would benefit from a comprehensive design strategy, a brand. Pick was very interested in art and design and believed that design had a civilising effect on people. Pick instigated a corporate typeface and logo; the famous LT 'roundel' which is still basically the same today. The design policy he oversaw reached every area of LT right down to the upholstery coverings.

One of Pick's great achievements was in the use of new and established artists to design posters. The London Transport poster collection includes work from famous artists such as Jacob Epstein and Man Ray.

When the Piccadilly line was extended Pick chose the architect Charles Holden to design a new type of station. One of these stations was Manor House in Hackney, which opened in 1932.

Perhaps the most famous design of the Pick era was Harry Beck's underground map designed in 1931. Beck designed his map after being inspired by electrical circuit diagrams. The Underground map has changed little from Beck's original design and has been used as a basis for transport maps from New York to St Petersburg and Sydney.