John Clute, Critic Guest of Honor at Readercon 4, was born in Canada in 1940, and has lived in England since 1969 in the same Camden Town flat. Since 1997, he has visited America yearly, spending much of his time with Elizabeth Hand in Maine. He received a Pilgrim Award from the SFRA in 1994, was Distinguished Guest Scholar at the 1999 International Conference for the Fantastic in the Arts, and received an SFWA Solstice Award in 2012.

He was Associate Editor of the Hugo-winning first edition (Doubleday, 1979) of the Encyclopedia of Science Fiction, general editor Peter Nicholls; co-edited the second edition (St. Martin's, 1993) with Nicholls, which won the Hugo, Locus, British SF Special, and the Eaton Grand Master Award; and is co-editor of the third edition (Gollancz, online 2011) with David Langford (Nicholls remaining Editor Emeritus) and Graham Sleight as Managing Editor, which has won the British SF Award for nonfiction, the 2012 Eurocon, and a Hugo Award for 2012.

He also co-edited the Encyclopedia of Fantasy (St. Martin's, 1997) with John Grant, which won the Hugo, Locus, Mythopoeic, and Eaton Awards, was a Stoker finalist, and won the editors the World Fantasy Special Award: Professional (Clute having been a finalist previously, for 1993 and 1994). On his own hook he wrote Science Fiction: The Illustrated Encyclopedia (Dorling Kindersley, 1995; Hugo and Locus winner, British SF finalist), which is actually a companion, not an encyclopedia. The Book of End Times: Grappling with the Millennium (HarperPrism) appeared in 1999.

Book reviews and other criticisms have been assembled in Strokes: Essays and Reviews 1966 - 1986 (Serconia, 1988; Readercon Award winner), Look at the Evidence: Essays and Reviews (Serconia, 1996; Locus winner, Hugo finalist), Scores: Reviews 1993-2003 (Beccon, 2003; Hugo and Locus finalist), Canary Fever: Reviews (Beccon, 2009; Hugo and British SF finalist) and Stay (Beccon, 2014). The Darkening Garden: A Short Lexicon of Horror (Payseur & Schmidt, 2006; Locus and International Horror Guild finalist) argues that horror—which is to say Planetary Recognition—is central to 21st century fantastika. The central pieces assembled in Pardon This Intrusion: Fantastika in the World Storm (Beccon, 2011) further this argument. He has published two novels: The Disinheriting Party (Allison and Busby, 1977), which is not sf, and Appleseed (Orbit/Little Brown/Tor, 2001; Tiptree finalist and New York Times Notable Book), which is sf.

Projects include further work on The Encyclopedia of Science Fiction, already more than a million words longer than the 2011 launch version.