Science Fiction: The 100 Best Novels, An English-Language Selection, 1949–1984 is a nonfiction book by David Pringle, published by Xanadu in 1985 with a foreword by Michael Moorcock.  Primarily, the book comprises 100 short essays on the selected works, covered in order of publication, without any ranking. It is considered an important critical summary of the science fiction field.
 Pringle followed Science Fiction with Modern Fantasy: The 100 Best Novels (1988). Xanadu followed Science Fiction with at least three more "100 Best" books (below).
 In the introduction Pringle offers the working definition, "Science fiction is a form of fantastic fiction which exploits the imaginative perspectives of modern science." In turn, modern science is the "scientific world-view ... as it has come to be accepted by the intelligent layperson", which arguably "first became common property in the mid to late 19th century."
 Within fiction he distinguishes science fiction from "Supernatural Horror" and "Heroic Fantasy". They may be represented by Dracula and The Lord of the Rings, featuring "the irruption of some supernatural force into the everyday world" and "set in completely imaginary worlds" respectively. He also names the subclass "Fabulations", which do not belong in this book "unless they have a significant scientific or technological content".
 In contrast, science fiction has a real-world setting and "fantastic developments which are explicable in terms of the scientific world-view." World-view does not mean accepted theory or fact: "many sf writers cheat: they use sleight-of-hand rather than genuine scientific knowledge." "The skilful use of pseudo-science and gobbledygook" may be good enough to exploit the world-view.
 The time period covered is approximately that for science fiction as a category of book publication, although the selected books were not all published in that category.
 
Pringle admits that fewer than thirty selections may generously be called even "masterpieces of their sort". On the whole, Some of them are old favourites of my own ... Some are other people's favourites, novels which have been outstandingly popular or influential, or which seem to be especially good representatives of their type. A small minority, perhaps as many as ten, are books for which I have little or no personal enthusiasm: they have been included for the sake of balance and variety. Xanadu Publications of London published at least four "100 Best" books. Transatlantic editions or simply jacket and cover designs may variably use "the" and "hundred" in the subtitles. Carroll & Graf published the books in the U.S.
 Xanadu commissioned Moorcock to write Fantasy. When it became "clear that I would not be able to deliver it for a long time, the publishers and I agreed that James Cawthorn was the person to take it over." Cawthorn was the primary author of the selections "mainly", according to Cawthorn, and of the text "by far", according to Moorcock. (Fantasy, "Introduction", p. 9. The introduction, pp. 8–10, comprises a long section signed by Cawthorn, a short one signed by Moorcock, and joint unsigned "Notes and Acknowledgments".)
 Science Fiction is a collection of 100 reviews, nearly uniform in length (all one to two pages), with a moderately long introduction by the author.
 Horror comprises essays on 100 different books by 100(?) horror writers, apparently more-than-one- to less-than-six pages in length.
 Fantasy is a collection of 100 reviews, nearly uniform in length (little short of two pages), with a short introduction by the authors separately and jointly.
 Dave Langford reviewed Science Fiction: The 100 Best Novels for White Dwarf #73, and stated that "Most of my favourites are there, and only a scattering of dodgy selections - like Mack Reynolds, an 'ideas and concepts' man whose writing makes my teeth hurt."