This anthology is worth noting for its ambitious claim of collecting the best science fiction of the 20th Century. Whether or not that’s entirely accurate, it does put together a pretty impressive list of stories to represent the field. From the “Golden Age” we have stories like “All You Zombies—“ by Heinlein, and Arthur C. Clarke’s “The Nine Billion Names of God.” From the “New Wave”, ““Repent, Harlequin!” Said the Ticktockman” by Harlan Ellison, and “Inconstant Moon” by Larry Niven. From the “Media Generation,” Lisa Goldstein’s “Tourists” and Terry Bisson’s “Bears Discover Fire.” These are only a few of over two dozen stories representing three eras of literary adventure and exploration. Is it the best? That’s always subjective. It’s certainly a collection of great stories, many of them classics, and well worth reading.