Each volume featured a number of novelettes and short stories, mostly new works by British and Commonwealth science fiction authors, with occasional pieces by American authors, together with a foreword by the editor. The first twenty volumes included forewords by Carnell, the twenty-first by Diane Loyd, and the twenty-second through the thirtieth by Kenneth Bulmer. The Carnell-edited volumes averaged seven pieces per volume; the Bulmer-edited volumes averaged eleven.
