This may be the book for which Ellison is best known -- and he was the editor, not the author.
"Editor "doesn't begin to describe the accomplishment here, which is quite astounding. Until Dangerous Visions, science fiction anthologies tended to be thin, both in content and quality: second-rate tales from seldom-read authors, gathered more or less at random and slapped between cheap paper covers bearing lurid illustrations that had nothing to do with the content within.
Ellison changed the rules. He solicited only unpublished works, and only from the most accomplished writers, both grand old masters and hot newcomers. Moreover, he urged his contributors to stretch, to challenge their own abilities, to offer something cutting edge that might scare off editors of the more conventional science fiction magazines.
He got what he was after. At the time of its publication, Dangerous Visions truly was dangerous. A good many of its stories remain fresh and daring today, nearly three decades hence -- particularly "Riders of the Purple Wage" by Phillip José Farmer and "Aye, and Gomorrah ..." by Samuel R. Delany.