American author of imaginative juvenile literature that is often concerned with such themes as the conflict of good and evil, the nature of God, individual responsibility, and family life.

L'Engle attended boarding schools in Europe and the United States and graduated with honours from Smith College (B.A., 1941). She pursued a career in the theatre before publishing her first book, The Small Rain (1945), a novel about an aspiring pianist who chooses her art over personal relationships. After writing her first children's book, And Both Were Young (1949), she began a series of juvenile fictional works about the Austin family—Meet the Austins (1960), The Moon by Night (1963), The Twenty-four Days Before Christmas (1964), The Young Unicorns (1968), and A Ring of Endless Light (1980).

In A Wrinkle in Time (1962; Newbery Medal, 1963), L'Engle introduced a group of young children who engage in a cosmic battle against a great evil that abhors individuality. Their story continues in A Wind in the Door (1973), A Swiftly Tilting Planet (1978), and Many Waters (1986). In addition to her fiction for juveniles, L'Engle also wrote several books of fiction and poetry for adults. She discussed her life and writing career in A Circle of Quiet (1972), The Summer of the Great-Grandmother (1974), The Irrational Season (1977), Walking on Water (1980), and Two Part Invention (1988).