Even many years after the original publication, Asimov's future history series remains popular—in the 1980s, forty years after he began the series, Asimov added a new volume, Foundation's Edge, and eventually linked the Foundation stories with his robot novels in The Robots of Dawn, Robots and Empire, Foundation and Earth, and Prelude to Foundation.

Asimov's first fiction written specifically for a younger audience was his "Lucky Starr" novels. In 1951, at the suggestion of his Doubleday editor, he began working on a series of science-fiction stories that could easily be adapted for television. "Television was here; that was clear," he writes in In Memory Yet Green. "Why not take advantage of it, then? Radio had its successful long-running series, `The Lone Ranger,' so why not a `Space Ranger' modeled very closely upon that?" David Starr: Space Ranger, published under the pseudonym Paul French, introduced David `Lucky' Starr, agent of the interplanetary law enforcement agency the Council of Science. Accompanying Lucky on his adventures is his sidekick, John Bigman Jones, a short, tough man born and raised on the great agricultural farms of Mars. Together the two of them confront and outwit space pirates, poisoners, mad scientists, and interstellar spies—humans from the Sirian star system, who have become the Earth's worst enemies.

Although the "Lucky Starr" series ran to six volumes, the television deal that Asimov and his editor envisioned never materialized. "None of us dreamed that for some reason .. television series would very rarely last more than two or three years," Asimov writes. "We also didn't know that a juvenile television series to be called `Rocky Jones: Space Ranger' was already in the works." Another problem the series faced was in the scientific background of the stories. "Unfortunately," state Jean Fiedler and Jim Mele in Isaac Asimov, "Asimov had the bad luck to be writing these stories on the threshold of an unprecedented exploration of our solar system's planets, an exploration which has immensely increased our astronomical knowledge. Many of his scientific premises, sound in 1952, were later found to be inaccurate." In recent editions of the books, Asimov has included forewords explaining the situation to new readers.

Asimov's first nonfiction book was a medical text entitled Biochemistry and Human Metabolism, begun in 1950 and written in collaboration with William Boyd and Burnham Walker, two of his colleagues at the Boston University School of Medicine. He had recognized his ability as an explainer early in life, and he enjoyed clarifying scientific principles for his family and friends. He also discovered that he was a most able and entertaining lecturer who delighted in his work as a teacher.