One of the major figures in science fiction for more than sixty years, James Gunn has been instrumental in making the genre one of the most vibrant and engaging areas of literary scholarship. His genre history Alternate Worlds and his The Road to Science Fiction anthologies introduced countless readers to science fiction. He founded the Gunn Center for the Study of Science Fiction in 1982. But Gunn has also been one of the genre's leading writers. His classic novels Star Bridge (with Jack Williamson), The Joy Makers, The Immortals and The Listeners helped shape the field. Now in his nineties, he remains a prominent voice. His forthcoming novel is Transformation. Drawing on materials from Gunn's archives and personal interviews with him, this study is the first to examine the life, career and writing of this science fiction grandmaster.