In 1953, he worked in Cairo for France Soir, before returning to Le Monde as director for the overseas services, and grand reporter (one of the highest titles in French journalism) until 1975.

He is interviewed in the 1968 documentary film about the Vietnam War entitled In the Year of the Pig.

Lacouture was also director for publication at Seuil, one of the main French publishers, from 1961 to 1982, and professor at the L'Institut d'Etudes Politiques de Paris (Sciences PO) between 1969 and 1972.

He was mainly known to the public because of his biographies, including the lives of Ho Chi Minh, Nasser, Léon Blum, De Gaulle, François Mauriac, Pierre Mendès France, Mitterrand, Montesquieu, Montaigne, Malraux, Germaine Tillion, Champollion, Jacques Rivière, Stendhal and Kennedy.

A dedicated music lover, Lacouture was also president of a society of devotees of Georges Bizet.