For decades beginning in the 1950s the US men's magazine Playboy was the source of more SF and fantasy stories than any magazine outside the genre. It included genre stories only occasionally, but paid well and thus attracted top writers; there are classic stories in the list below by Ballard, Bradbury, Clarke, Knight, Le Guin, and others. (At the same time, Clarke's longish "A Meeting with Medusa" has never been included in any of these anthologies.)
In the mid-1960s the magazine's own book publishing arm released three anthologies, two hardcover and one paperback, all credited anonymously to "the editors of Playboy" though both SFE and Isfdb credit Ray Russell. Then in 1971 eight mass market paperbacks with matching cover designs were released, reprinting some of the stories in the earlier books and adding many more, again anonymously edited. (Five are shown in the photo.)
Finally in 1998 long-time Playboy fiction editor Alice K. Turner published an anthology of 25 stories from 1965 to 1997, half of them from years following 1971, with Harper Prism.
Authors most often reprinted: Robert Sheckley (13), then Charles Beaumont, Ray Bradbury, Arthur C. Clarke, Ray Russell, and Henry Slesar (9 each).
The Playboy Book of Science Fiction and Fantasy, (Playboy, 1966)
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The Playboy Book of Horror and the Supernatural, (Playboy, 1967)
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Playboy's Stories of the Sinister & Strange, (Playboy, 1969)
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Fully Automated Love Life of Henry Keanridge, (Playboy, 1971)
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