Night and Day is a novel by Virginia Woolf first published on 20 October 1919. Set in Edwardian London, Night and Day contrasts the daily lives and romantic attachments of two acquaintances, Katharine Hilbery and Mary Datchet. The novel examines the relationships between love, marriage, happiness, and success.

The novel has four major characters: Katharine Hilbery, Mary Datchet, Ralph Denham, and William Rodney. Night and Day deals with questions concerning women’s suffrage, and asks whether love and marriage can coexist and whether marriage is necessary for happiness. Motifs throughout the book include the stars and sky, the River Thames, and walks. Woolf makes many references to the works of William Shakespeare, especially As You Like It.