In 1900 an American financier called Charles Tyson Yerkes was placed in charge of London's underground railways, which had been in service since 1863 and were, even then, showing signs of their age. Over the next five years he applied his business methods – which he described as 'Buy up old junk, fix it up a little and unload it upon other fellows' – to the construction of much of the capital's deep-level tube system. Yerkes was one of many colourful characters who gave London its underground railway system. But the London Underground is more than a railway. In the twentieth century, under the enlightened management of Frank Pick, the Underground was responsible for some striking developments in industrial design. Bauhaus, Cubist and other innovative ideas were applied to station architecture, advertising posters and seat covers. The work of artists such as Graham Sutherland, Len Deighton and Lucie Attwell was exposed to large audiences for the first time, as was that icon of industrial design, Harry Beck's diagrammatic map of the Underground network. Making use of extensive research in London's archives, Stephen Halliday shows how these pioneers struggled with the problem that vexes the Underground to this day. London undoubtedly needs it but has never really decided who should pay for it. Passengers or taxpayers? Public or private finance? Is it a profit-making enterprise or a social service? The book places this unanswered question in its historical context as, in the twenty-first century, the debate turns in a new direction, once again headed by an American under the direction of London's first elected mayor.