Jacques-Marie-Émile Lacan was a French psychoanalyst, psychiatrist, and doctor, who made prominent contributions to the psychoanalytic movement. His yearly seminars, conducted in Paris from 1953 until his death in 1981, were a major influence in the French intellectual milieu of the 1960s and 1970s, particularly among post-structuralist thinkers.

Lacan's ideas centered on Freudian concepts such as the unconscious, the castration complex, the ego, focusing on identifications, and the centrality of language to subjectivity. His work was interdisciplinary, drawing on linguistics, philosophy, mathematics, amongst others. Although a controversial and divisive figure, Lacan is widely read in critical theory, literary studies, and twentieth-century French philosophy, as well as in the living practice of clinical psychoanalysis.