Presidential Medal of Distinction

NAACP Image Award – Chairman's Award

National Medal of Science

Order of Sikatuna

NAACP Image Award for Outstanding Literary Work, Nonfiction

honorary member

Nebula Award for Best Novelette

Locus Award for Best Fantasy Novel

Hugo Award for Best Novelette

WSFA Small Press Award

World Fantasy Award for Life Achievement

Grand Prix de l'Imaginaire

World Fantasy Special Award: Non-Professional

World Fantasy Award for Best Anthology

World Fantasy Special Award: Professional

Fellow of the Institution of Engineering and Technology

Fellow of the British Computer Society