information:classification, structural:expansion, quality:corruption
Posters and patronage of the arts

Early advertising posters used various typefaces. Graphic posters first appeared in the 1890s, and it became possible to print colour images economically in the early 20th century. The Central London Railway used colour illustrations in their 1905 poster, and from 1908 the Underground Group, under Pick's direction, used images of country scenes, shopping and major events on posters to encourage use of the tube. Pick found he was limited by the commercial artists the printers used, and so commissioned work from artists and designers such as Dora Batty, Edward McKnight Kauffer, the cartoonist George Morrow, Herry (Heather) Perry, Graham Sutherland, Charles Sharland and the sisters Anna and Doris Zinkeisen. According to Ruth Artmonsky, over 150 women artists were commissioned by Pick and latterly Christian Barman to design posters for London Underground, London Transport and London County Council Tramways.

The Johnston Sans letter font began appearing on posters from 1917. The Met, strongly independent, used images on timetables and on the cover of its Metro-land guide that promoted the country it served for the walker, visitor and later the house-hunter. By the time London Transport was formed in 1933 the UERL was considered a patron of the arts and over 1000 works were commissioned in the 1930s, such as the cartoon images of Charles Burton and Kauffer's later abstract cubist and surrealist images. Harold Hutchison became London Transport publicity officer in 1947, after the Second World War and nationalisation, and introduced the "pair poster", where an image on a poster was paired with text on another. Numbers of commissions dropped, to eight a year in the 1950s and just four a year in the 1970s, with images from artists such Harry Stevens and Tom Eckersley.

Art on the Underground was launched in 2000 to revive London Underground as a patron of the arts. Today, commissions range from the pocket Tube map cover, to temporary artworks, to large-scale permanent installations in stations. Major commissions by Art on the Underground in recent years have included Labyrinth by the Turner Prize –winning artist Mark Wallinger, to mark the 150th anniversary of the Underground; Diamonds and Circles, permanent works in situ by the French artist Daniel Buren at Tottenham Court Road; and Beauty < Immortality, a memorial to Frank Pick by Langlands & Bell at Piccadilly Circus.

Similarly, since 1986 Poems on the Underground has commissioned poetry that is displayed in trains.