John Keith Laumer (June 9, 1925 - January 23, 1993) was an American science fiction author.
He is best known for his Bolo stories, concerning self-aware juggernaut-sized tanks with awesome firepower in the range of Megatons/second, and for his satirical Retief series, about a two-fisted diplomat who is constantly having to overcome the red-tape-infused failures of people with names like Ambassador Grossblunder; the latter were greatly influenced by his longtime career in the United States Diplomatic Corps.
Four of his short stories received Hugo or Nebula Award nominations (one of them, "In the Queue", received nominations for both), and his novel A Plague of Demons was nominated for the Nebula Award for Best Novel.
In , Laumer suffered a stroke while writing his novel The Ultimax Man, after which the quality of his work dropped precipitously. It is said that a sufficiently skilled neurologist can correctly assess what parts of Laumer's brain were affected by the stroke, solely by reading his pre- and post-stroke writing.