In 1999 the British Film Institute invited a large amount of people working within the film and television industry to take part in finding the 100 top British films of the 20th century.
Source: http://www.imdb.com/list/pVQCkiZoP9c/
35 movies missing from source.
The BFI 100 - A selection of the favourite British films of the 20th Century
by sp1tiVIP OG 13