Created originally to provide anthologies for use in classes, these volumes have become mass-market sellers as well, since they are not only a source of outstanding stories, but also explain what constitutes science fiction, how it developed, and the contribution the authors and the stories have made to the evolution of science fiction. The editor, noted author and scholar James Gunn, believes that science fiction is best understood and appreciated in the context of its historical development.

Volume 3, From Heinlein to Here, covers the period from 1940 to 1975, beginning in the Golden Age of Science Fiction and ending at a time when SF book publication was just beginning to explode and SF films (2001: A Space Odyssey; Close Encounters of the Third Kind, Star Wars, E.T.) would soon dominate box offices.