The Great Houses (tuqmey Dun) were a Klingon feudalistic social organization that dominated the Klingon Empire. Each House was usually led by the eldest male of the ruling family, for whom the House was named. His wife was the Mistress of the Great House, who usually oversaw the running of the household and approved all marriages into the family. Traditionally, the ruling family was of noble descent. In the late 24th century, however, that was not always the case. The Great House also included various properties and holdings, and commanded military forces. The rulers of the twenty-four most powerful Great Houses formed the Klingon High Council.
When the head of a Great House died, either in battle or of natural causes, leadership of the House passed to his heir, usually his son. If the head of the House had been defeated in honorable combat, his wife had the right to choose his victor as the new head of her House (see also: brek'tal ritual). If the head of the House left no male heir, the High Council could arrange special dispensation for someone else to rule the House, such as the Mistress. (DS9: "The House of Quark") It was possible for individuals unrelated by blood to join a Great House, by consent of the House's head. (TNG: "The Bonding"; DS9: "Soldiers of the Empire"; see also: R'uustai)
Great Houses which were gravely dishonored by the actions of their rulers could be disbanded, and their holdings claimed by other Houses.
- House of Antaak
- House of D'Ghor
- House of Duras
- House of Grilka (temporarily "House of Quark", formerly House of Kozak)
- House of Konjah
- House of Kor
- House of Martok
- House of Mo'Kai
- House of Mogh
- House of Noggra
Ronald D. Moore stated, "We've never explored the hows and whys regarding the naming of Klingon Houses. The House of Mogh reference was probably something that Worf carried on out of respect for his deceased father. This might be the right of a son – to perpetuate a single name for the House instead of supplanting it with his own." (AOL chat, 1997)
The episode "The Bonding" turned out to be the conceptual genesis of Klingon Houses. Recalling his writing of the installment, Ron Moore explained, "I started thinking about [...] Houses, and sort of, you know, the idea of bonding people to a Klingon House [....] The idea of bloodlines and families and sort of this Shakespearian idea of how the Klingon Empire ran – I was starting to, sort of, deal with that in this episode." Moore reckoned, "I think I used the word 'House' in my draft [of 'The Bonding'], even though it's not in the episode." (The Bonding" audio commentary, TNG Season 3 Blu-ray) Neither is the term included in the third revised draft of the installment's script. 
Ron Moore's concept of the conflicting, family-organized Great Houses was inspired by the Dune mythology created by Frank Herbert. In a Klingon-defining memo which Moore sent to Michael Piller at the outset of working on "Sins of the Father", Moore stated, "A Klingon regards the honor of his or her family to be valuable, above all else. The family name can be besmirched by any member of the family, regardless of age or infirmity. A Klingon would sooner kill himself and his closer brother than live with a mark on the name of his ancestral lineage. The family is all, and a member of the family is responsible for the actions of his kin. The oldest son of a Klingon warrior may be called upon to give his life for the actions of his father." The same document also referred to certain families being of importance in the Klingon Empire, the leaders of which comprised the High Council. ("Sins of the Father" audio commentary, TNG Season 3 Blu-ray)