Barbu (or Barbuda) is a four-player trick-taking card game of French origin. Each of the four players in turn becomes declarer. The declarer picks one of seven contracts for each hand. No contract is repeated until all seven have been played. Many variants of Barbu are played which include different contracts and point schedules, but seven common contracts are:

• Barbu (don't take king of hearts)
• Hearts (don't take hearts)
• Last Two (don't take last two tricks)
• Nullo (don't take tricks)
• Queens (don't take queens)
• Trumps (take tricks)
• Fan Tan (be first out of cards)

See also Coup d'État, Dragonmaster and Guillotine.
See also The Dwarf King, Indulgence, and Phobos Infection: The Lost Journey of X27