Patrick Nielsen Hayden, often abbreviated as PNH, is an American science fiction editor, fan, fanzine publisher, essayist, reviewer, anthologist, teacher and blogger. He is a World Fantasy Award and Hugo Award winner (with nine nominations for the latter award), and is a Senior Editor and the Manager of Science Fiction at Tor Books. He changed his last name to "Nielsen Hayden" on his marriage to Teresa Nielsen (now Teresa Nielsen Hayden) in 1979.