From the "About the Author" page in "The Siege of Eternity":

A mutliple Hugo and Nebula Award-winning author, Frederik Pohl has done just about everything one can do in the science-fiction field.  His most famous work is undoubtedly the novel Gateway, which won the Hugo, Nebula, and John W. Campbell Memorial Awards for best SF novel.  Man Plus won the Nebula Award.  His mature work is marked by a serious intellectual agenda and strongly held sociopolitical beliefs, without sacrificing narrative drive.  In addition to his successful solo fiction, Pohl has collaborated successfully with a variety of writers, including C. M. Kornbluth and Jack Williamson.  A Pohl/Kornbluth collabortation, The Space Merchants, is a long-time classic of satiric science fiction.  The Starchild Trilogy with Williamson is one of the more notable collaborations in the field.  Pohl has been a magazine editor in the field since he was very young, piloting World of If to three successive Hugos for Best Magazine.  He also has edited original-story anthologies, including the early and notable Star series of the early 1950s.  He has at various times been a literary agent, and editor of lines of science fiction books, and a president of the Science Fiction Writers of America.  For a number of years he has been active in the World SF movement.  He and his wife, Elizabeth Anne Hull, a prominent academic active in the Science Fiction Research Association, live outside Chicago, Illinois.