Originally published in 1957, this is the second of Isaac Asimov's robot-mystery novels. It marked the beginning of a hiatus in his output of adult science fiction novels, as he turned his primary writing efforts into non-fiction for awhile.
It's an odd future. Although interstellar travel has been invented, it's restricted to the Spacers, who have control of 50 planets. They maintain a semi-hostile relationship with Earth. But a murder of a "fetologist" on the planet Solaria causes the humanoid robot detective, R. Daneel Olivaw, to arrange for his old Earthman partner, Elijah Baley, to join the investigation.
Asimov does a fine job of world-building. Earthmen have adapted to a completely enclosed urban existence, most never even seeing the outdoors, let alone venturing there; the very notion gives them the creepy crawlies.
Solaria has developed a different set of phobias. Humans are vastly outnumbered by robots, who do nearly all the work. The human population is strictly capped at 20,000; nobody can be born unless someone dies. And the Solarians lead a totally isolated existence, to the point that physical proximity to another human makes them uncomfortable, even frantic. Baley's efforts to track down the perpetrator are hampered by his total unfamiliarity with Solarian society. But eventually, he determines the culprit, and rough justice is delivered.
Daneel is unfortunately absent through much of the book; when he shows up, he's relatively passive. I would have enjoyed more Daneel, but it's tough to argue with a book that's sold bajillions of copies.