With Mikhail Ahmanov:

• Deathworld 7

With Brian W. Aldiss:

• Hell's Cartographers: Some Personal Histories of Science Fiction Writers
• Science Fiction Horizons, 2 Volumes in 1
• The Astounding-Analog Reader, Volume 1
• The Astounding-Analog Reader, Volume 2
• Best SF: 1967
• Best SF: 1968
• Best SF: 1969
• Best SF: 1970
• Best SF: 1971
• Best SF: 1972
• Best SF: 1973
• Best SF: 1974
• Best SF: 1975, the Ninth Annual
• Decade, the 1940s
• Decade, the 1950s
• Decade, the 1960s
• Farewell, Fantastic Venus! A History of the Planet Venus in Fact and Fiction
• Nebula Award Stories 2

With David Bischoff:

• Bill, the Galactic Hero on the Planet of Tasteless Pleasure
• Bill, the Galactic Hero on the Planet of Ten Thousand Bars

Illustrated by Jim Burns:

• Planet Story

With Gordon R. Dickson:

• Lifeboat

With Malcolm Edwards:

• Spacecraft in Fact and Fiction

With Theodore J. Gordon:

• Ahead of Time: Noted Scientists Prove That Truth Can Be Stranger Than Fiction

With Jack C. Haldeman II:

• Bill, the Galactic Hero on the Planet of Zombie Vampires

With David Harris:

• Bill, the Galactic Hero: the Final Incoherent Adventure

With John Holm:

• The Hammer and the Cross
• One King's Way
• King and Emperor

With Bruce McAllister:

• There Won't Be War

With Katherine MacLean:

"Web of the Worlds"

With Willis E. McNelly:

• Science Fiction Novellas

With Barry N. Malzberg:

"The Whatever-I-Type-Is-True Machine"

With Marvin Minsky:

• The Turing Option

With Hubert Pritchard:

"Open All Doors"

With Carol Pugner:

• A Science Fiction Reader

With Robert Sheckley:

• Bill, the Galactic Hero on the Planet of Bottled Brains

With Tom Shippey:

"A Letter from the Pope"

With Ant Skalandis:

• Return to Deathworld
• Deathworld vs. Filibusters
• The Creatures from Hell

• Stonehenge
• Stonehenge: Where Atlantis Died
• Apeman, Spaceman: Anthropological Science Fiction