A collection of seven short stories (a couple of which I believe are actually novelettes). For the most part they're fairly interesting and I enjoyed them, although the robot stories I prefer from Asimov star Susan Calvin rather than the continually complaining duo of Donovan and Powell. Still, the three robot stories here are likeable enough, certainly better than "Death Sentence" (only marginally robotic) and "Marooned off Vesta", both of which were pretty average. The real stand-out, though, is "Nightfall". This was eventually turned into a novel, if I recall correctly, and it's a really fascinating thought experiment about a society that evolved in a multi-star system and subsequently never experienced darkness... except in times of periodic eclipse, which every few thousand years is the cause of mass psychological breakdown and apocalypse, essentially. The collection's worth reading for that story alone, I reckon.