Lady Susan is a short epistolary novel by Jane Austen possibly written in 1794 but not published until 1871. This early complete work which the author never submitted for publication describes the schemes of the title character.

Lady Susan Vernon a beautiful and charming recent widow visits her brother- and sister-in-law Charles and Catherine Vernon with little advance notice at Churchill their country residence. Catherine is far from pleased as Lady Susan had tried to prevent her marriage to Charles and her unwanted guest has been described to her as "the most accomplished coquette in England". Among Lady Susan's conquests is the married Mr. Manwaring.

Catherine's brother Reginald arrives a week later and despite Catherine's strong warnings about Lady Susan's character soon falls under her spell. Lady Susan toys with the younger man's affections for her own amusement and later because she perceives it makes her sister-in-law uneasy. Her confidante Mrs. Johnson to whom she writes frequently recommends she marry the very eligible Reginald but Lady Susan considers him to be greatly inferior to Manwaring.