Collaborations with Kate Wilhelm

• The Clone (1965, expanded from his 1959 short story of the same name)
• The Year of the Cloud (1970)

• "The Far Look", in Astounding, August 1956
• "Ceramic Incident", in Astounding, October 1956
• "The Innocents’ Refuge", in Science Fiction Stories, May 1957
• "Satellite Passage", in If, Dec 1958, and available in The Best of the Best Part One
• "Day of Succession", in Astounding, August 1959
• "The Clone", in Fantastic, Dec 1959
• "December 28th", in Playboy, Dec 1959
• "The Intruder", in Fantasy and Science Fiction, Feb 1961
• "Test", in Fantasy and Science Fiction, April 1962
• "The Lonely Man", in Galaxy, April 1963
• "The Ice Ages", in Fantasy and Science Fiction, April 1965
• "Science Springboard, The: Smog", article in Fantasy and Science Fiction, Jan 1966
• "The Doctor", in Orbit 2, 1967
• "The Weather on the Sun", in Orbit 8, 1970 (Also available in The Science Fictional Solar System)
• "Early Bird ", in Astounding, 1973 (Also available in The John W Campbell Memorial Anthology)
• Ker-Plop, in Asimov's Science Fiction, 1979
• "The Splice", in Fantasy and Science Fiction, March 1981

As Cogswell Thomas

• "Paradise Regained", in Saving Worlds, 1973

As Leonard Lockard

• "The Lagging Profession" (1961)
• "Improbable Profession" (1952), in Astounding, September 1952 (co-written with Charles L. Harness)