Masters of the science fiction story have been advising initiates on the form almost since the birth of the genre. Here some of the earliest such masters from the 1940s and 1950s, both authors and editors, render their commentary and advice on how to write outstanding science fiction stories. Contributors include Robert Bloch, Ross Rocklynne, Leigh Brackett, August Derleth, Fritz Leiber, John W. Campbell, Margaret St. Clair, Col. S. P. Meek, Manley Wade Wellman, Shirley Jackson, Martin Gardner, Robert Moore Williams, Isaac Asimov, Sam Merwin, Jr., and Mack Reynolds. Their commentary and advice is as timely and useful now as it was when first rendered.