The Fabian Society is a British intellectual socialist movement, whose purpose is to advance the principles of social democracy via gradualist and reformist, rather than revolutionary means. It is best known for its initial ground-breaking work beginning late in the 19th century and continuing up to World War I. The society laid many of the foundations of the Labour Party and subsequently affected the policies of states emerging from the decolonisation of the British Empire, especially India. Today, the society is a vanguard "think tank" of the New Labour movement. It is one of 15 socialist societies affiliated to the Labour Party. Similar societies exist in Australia (the Australian Fabian Society), Canada (the Douglas-Coldwell Foundation and in past the League for Social Reconstruction) and New Zealand.
Fabian Society began attracting many prominent contemporary figures drawn to its socialist cause, including George Bernard Shaw, H. G. Wells, Annie Besant, Graham Wallas, Hubert Bland, Edith Nesbit, Sydney Olivier, Oliver Lodge, Leonard Woolf and Virginia Woolf, Ramsay MacDonald and Emmeline Pankhurst. Even Bertrand Russell briefly became a member, but resigned after he expressed his belief that the Society's principle of entente (in this case, countries allying themselves against Germany) could lead to war.