A fix-up (or fixup) is a novel created from several short fiction stories that may or may not have been initially related or previously published. The stories may be edited for consistency, and sometimes new connecting material, such as a frame story or other interstitial narration, is written for the new work. The term was coined by the science fiction writer A. E. van Vogt, who published several fix-ups of his own, including The Voyage of the Space Beagle, but the practice (if not the term) exists outside of science fiction. The use of the term in science fiction criticism was popularised by the first (1979) edition of the Encyclopedia of Science Fiction, edited by Peter Nicholls, which credited van Vogt with the creation of the term. The name comes from the modifications that the author needs to make in the original texts to make them fit together as though they were a novel. Foreshadowing of events from the later stories may be jammed into an early chapter of the fix-up, and character development may be interleaved throughout the book. Contradictions and inconsistencies between episodes are usually worked out.
Some fix-ups in their final form are more of a short story cycle or composite novel rather than a traditional novel with a single main plotline. Examples are Ray Bradbury's The Martian Chronicles and Isaac Asimov's I, Robot, both of which read as a series of short stories which may share plot threads and characters but which still act as self-contained stories. By contrast, van Vogt's The Weapon Shops of Isher is structured like a continuous novel although it incorporates material from three previous Van Vogt short stories.
Fix-ups became an accepted practice in American publishing during the 1950s, when science fiction and fantasy—once published primarily in magazines—began appearing increasingly in book form. Large book publishers like Doubleday and Simon & Schuster entered the market, greatly increasing demand for fiction. Authors created new manuscripts from old stories to sell to publishers. Algis Budrys in 1965 described fixups as a consequence of the lack of good supply during the "bad years for quality" of the mid-1950s, although citing The Martian Chronicles and Clifford D. Simak's City as among exceptions.