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. Dialogue and descriptions of thought and actions are used in equal amount, unlike in Woolf's later book, To the Lighthouse. There are four major characters, Katharine Hilbery, Mary Datchet, Ralph Denham, and William Rodney.