Ace Books was founded in 1953 by the editor and publisher A. A. Wyn. It was acquired by G. P. Putnam's Sons in 1982 becoming an imprint of Berkley's. Currently an imprint of Penguin, Ace Books holds the distinction of being the longest continuously running science fiction publisher in the USA. Over the years it has published works by some of the most revered names in science fiction and fantasy including Samuel R. Delany, Philip K. Dick, Ursula K. Le Guin, and Robert Silverberg and more recently Joe Haldeman, Jack McDevitt, Charlaine Harris, Laurell K. Hamilton and Jim Butcher.
Ace Books also innovated too, creating the well known "Ace Doubles" which featured two short novels published back to back within the same book.