U.S. diplomat and intelligence expert, who was director (1953–61) of the Central Intelligence Agency (CIA) during its early period of growth.

The younger brother of U.S. Secretary of State John Foster Dulles (Dulles, John Foster), Allen Dulles received an M.A. from Princeton in 1916 and then served in various diplomatic posts until 1922, when he was named chief of the State Department's Near Eastern Division. After receiving a law degree in 1926, he served briefly as counselor to the U.S. delegation in Beijing and then joined the New York law firm of which his brother was a member.

When the United States entered World War II, Dulles was recruited by Colonel William J. Donovan (Donovan, William J) for the Office of Strategic Services (OSS), an intelligence service. From October 1942 to May 1945 he served as chief of the OSS office in Bern, playing, in particular, a notable role in the events that led to the surrender of German troops in northern Italy.

In 1948 Dulles was made chairman of a three-man committee charged with surveying the U.S. intelligence system. After the CIA was established in 1951, he served as deputy director under General Walter Bedell Smith (Smith, Walter Bedell), and in 1953 he was appointed director by President Dwight D. Eisenhower (Eisenhower, Dwight D.). The agency was effective in a number of major operations, notably the overthrow of the governments of Mohammad Mosaddeq (Mosaddeq, Mohammad) in Iran in 1953 and Jacobo Arbenz (Arbenz (Guzmán), Jacobo) in Guatemala in 1954. It also succeeded in obtaining a copy of Nikita Khrushchev (Khrushchev, Nikita Sergeyevich)'s secret speech of 1956 denouncing Joseph Stalin. It was, however, embarrassed by the downing of a U-2 intelligence plane over the Soviet Union (Central Intelligence Agency) on the eve of a scheduled summit conference in June 1960.

Reappointed by President John F. Kennedy (Kennedy, John F.), Dulles was implicated in the failure of the Bay of Pigs invasion of Cuba in April 1961 and resigned that autumn. He was the author of many articles and a number of books on foreign affairs, notably Germany's Underground (1947), The Craft of Intelligence (1963), and The Secret Surrender (1966).