Throughout its history, many of the finest and most important works of science fiction have been short stories. Magazines and anthologies have been the lifeblood of the genre for at least 90 years. Magazines like Amazing or Astounding or Asimov's, anthologies like Universe or New Dimensions or Orbit, all deserve a place in any top 100 of the genre. But of all the short story collections the one that surely can't be ignored is Harlan Ellison's groundbreakingDangerous Visions, along with its even more massive companion, Again, Dangerous Visions.The 33 stories in Dangerous Visions won two Hugo Awards and two Nebula Awards; the 42 stories in Again, Dangerous Visionsadded another couple of Hugo and Nebula Awards. But the awards really don't tell the full story.What you find here are writers as varied as Frederik Pohl, Robert Bloch, Larry Niven, Roger Zelazny, Carol Emshwiller, Theodore Sturgeon, Norman Spinrad, Joanna Russ, Gene Wolfe, Kurt Vonnegut, Gregory Benford, Josephine Saxton, Thomas Disch, James Tiptree, Jr., and so on. It's a who's who of the very best science fiction writers, producing some of their very best work."Aye, And Gomorrah" by Samuel R. Delany, in which neutered spacers exploit their androgyny as a sexual fetish for others, is undoubtedly one of the finest stories he ever wrote. "The Word for World is Forest" by Ursula K. Le Guin, in which humans try to exploit the resources of an idyllic world uncaring of the harm it will do to the native inhabitants, is a glorious piece of work.Because Ellison encouraged his contributors to break taboos, to try things that science fiction hadn't done before, it resulted in some of the most original, challenging and brilliant stories in the genre. The two collections together were groundbreaking. Science fiction hadn't seen anything like them before, and hasn't seen anything like them since. The collection defined the American new wave, and changed the genre for a generation.