Stephen Reeder Donaldson (born May 13, 1947) is an American fantasy, science fiction, and mystery novelist, most famous for The Chronicles of Thomas Covenant, his ten-novel fantasy series. His work is characterized by psychological complexity, conceptual abstractness, moral bleakness, and the use of an arcane vocabulary. He has attracted critical praise for his imagination, vivid characterizations, and fast pace.

Stephen was born in Cleveland, Ohio. His father, James, was a medical missionary, and his mother, Ruth, a prosthetist. Donaldson spent the years between the ages of 3 and 16 living in India, where his father worked as an orthopedic surgeon.

He earned his bachelor's degree from The College of Wooster and a master's degree from Kent State University. Stephen R. Donaldson currently resides in Albuquerque, New Mexico.