Sir Richard Stafford Cripps (24 April 1889 – 21 April 1952) was a British Labour politician and Chancellor of the Exchequer for several years after the Second World War.

Cripps was born in London. His father was a Conservative member of the House of Commons who late in life, as Lord Parmoor, joined the Labour Party. Cripps grew up in a wealthy family and received the benefits of an aristocratic upbringing. He was educated at Winchester College and at University College, London, where he studied chemistry. He left science for the law, and in 1912 was called to the bar as a barrister. He served in the First World War as an ambulance driver in France and also successfully managed a factory producing armaments.

At the end of the 1920s, Cripps moved to the far left in his political views and in 1930 he joined the Labour Party. The next year, Cripps was appointed Solicitor-General in the second Labour government. This post was customarily accompanied by a knighthood, making him Sir Stafford Cripps. He was not yet a Member of Parliament, so he stood for and was elected in a by-election for the solidly Labour seat of Bristol East. He moved rapidly to the left and became an outspoken socialist and a strong proponent of Marxist social and economic policies. Although his strong faith in evangelical Christianity prevented him from subscribing to the Marxist rejection of religion, he enthusiastically advocated Marxist economic views of government control of the means of production and distribution.

In the 1931 general election, Cripps was one of only three former Labour ministers to hold their seats and so became the number three in the Parliamentary Labour Party, under the leader George Lansbury and deputy leader Clement Attlee. In 1932 he was one of the founders of the Socialist League, composed largely of members of the Independent Labour Party who rejected its decision to disaffiliate from Labour. The Socialist League put the case for an austere form of democratic socialism. Tall, thin and intense, he became the archetype of the British upper-class doctrinaire socialist so common in the 1930s.

In 1936, the National Executive Committee decided to dissociate itself from a speech in which Cripps said he did not "believe it would be a bad thing for the British working class if Germany defeated us". Cripps was an early advocate of a United Front against the rising threat of fascism. In 1936, he was the moving force behind a Unity Campaign, involving the Socialist League, the ILP and the Communist Party of Great Britain, designed to forge electoral unity against the right. Opposed by the Labour leadership, the Unity Campaign was a damp squib: Cripps dissolved the Socialist League in 1937 rather than face expulsion from Labour, though Tribune, set up as the campaign's propaganda organ and bankrolled by Cripps and George Strauss, survived (and survives to this day).

After the Hitler-Stalin pact, Joseph Stalin instructed the Comintern to oppose anti-Hitler policies in other countries as an attempt to engineer an "imperialist' war". In 1939, however, Cripps was expelled from the Labour Party for his advocacy of a Popular Front with the Communist Party and anti-appeasement Liberals and Conservatives.

When Winston Churchill formed his wartime coalition government in 1940, he appointed Cripps (a long-time cross-party colleague) ambassador to the Soviet Union, in the (perhaps naive) view that Cripps, an avowed Marxist, was the best person to try to negotiate with Stalin, who was at this time allied with Nazi Germany through the Molotov-Ribbentrop Pact. Cripps led a mission to Moscow in 1940 and unsuccessfully attempted to warn Stalin of the possibility of an attack by Hitler on the Soviet Union. When Hitler attacked in June 1941, Cripps became a key figure in forging an alliance between the western powers and the Soviet Union.

In 1942 Cripps returned to Britain and made a broadcast about the Russian war effort. The popular response was phenomenal, and Cripps rapidly became one of the most popular politicians in the country, despite having no party backing. He was appointed a member of the war cabinet, with the jobs of Lord Privy Seal and Leader of the House of Commons — perhaps a deliberate overpromotion by Churchill, as Prime Minister, designed to diminish his standing, as he was considered for a short period of time after his return from the Soviet Union as perhaps nearly a rival to Churchill in his hold on the country. He was sent to India on what is known as the Cripps Mission to attempt to negotiate an agreement with the nationalist leaders Gandhi and Jinnah that would keep India loyal to the British war effort in exchange for a promise of full self-government after the war. No formal agreement was reached. Later in 1942 he stepped down from being Leader of the House of Commons and was appointed Minister for Aircraft Production, a position outside of the War Cabinet but in which he served with substantial success. In 1945 Cripps rejoined the Labour Party.

When Labour won the general election of 1945, Clement Attlee appointed Cripps President of the Board of Trade, the second most important economic post in the government. Although still a strong socialist, Cripps had modified his views sufficiently to be able to work with mainstream Labour ministers. In Britain's desperate postwar economic circumstances, Cripps became associated with the policy of "austerity." As an upper-class socialist he held a puritanical view of society, and took a grim pleasure in enforcing rationing with equal severity against all classes.

In 1946, Soviet jet engine designers approached Stalin with a request to purchase jet designs from Western sources in order to overcome design difficulties. Stalin is said to have replied: "What fool will sell us his secrets?" However, he gave his assent to the proposal, and Soviet scientists and designers travelled to the United Kingdom to meet with Cripps and request the engines. To Stalin's amazement, Cripps and the Labour government were perfectly willing to provide technical information on the Rolls-Royce Nene centrifugal-flow jet engine designed by RAF officer Frank Whittle, along with discussions of a license to manufacture Nene engines themselves. The Nene engine was promptly reverse-engineered and produced in modified form as the Soviet Klimov VK-1 jet engine, later incorporated into the MiG-15 which flew in time to deploy in combat against UN forces in North Korea in 1950, causing the loss of several B-29 bombers and cancellation of their daylight bombing missions over North Korea.

In 1946, Cripps returned to India as part of the so-called Cabinet Mission, which proposed various formulas for independence to the Indian leaders. The other two members of the delegation were Lord Pethick-Lawrence, the Secretary of State for India, and A. V. Alexander, the First Lord of the Admiralty. However, the solution devised by the three men, known as the Cabinet Mission Plan, was unsatisfactory to the Indian National Congress (Gandhi is believed to have quipped that it was a "postdated cheque on a failing bank"), and India travelled further down the road which eventually led to Partition.

In 1947 amidst a growing economic and political crisis, Cripps tried to persuade Attlee to retire in favour of Ernest Bevin; however, Bevin was in favour of Attlee remaining. Cripps was instead appointed to the new post of Minister for Economic Affairs. Six weeks later Hugh Dalton resigned as Chancellor of the Exchequer and Cripps succeeded him, with the position of Minister for Economic Affairs now merged into the Chancellorship. Cripps laboured tirelessly to rescue Britain from its economic crisis. He increased taxes and forced a reduction in consumption in an effort to boost exports and stabilise the Pound Sterling so that Britain could trade its way out of its crisis. He strongly supported the nationalisation of strategic industries such as coal and steel.

Although Cripps's severe manner and harsh policies made him very unpopular, he won respect for the sincerity of his convictions and his tireless labours for Britain's recovery. His name once induced an infamous Spoonerism when the BBC announcer Macdonald Hobley introduced him as 'Sir Stifford Crapps'.

Cripps had suffered for many years from Colitis, inflammation of the lower bowel, a condition aggravated by excessive stress. In 1950 his health broke down under the strain and he was forced to resign his office in October. He resigned from Parliament the same month, and at the resulting by-election on 30 November he was succeeded as MP for Bristol South East by Tony Benn. Cripps died two years later while recuperating in Switzerland.

Cripps was the nephew of Beatrice Webb. He was the father of children's author Peggy Cripps, who shocked much British opinion at the time by marrying a black African, and grandfather of her son, philosopher Anthony Appiah.

Cripps was a vegetarian, certainly for health reasons and possibly also for humanitarian / ethical reasons. "Cripps suffered from recurring illness which was alleviated by nature cure and a vegetarian diet...".