The Complete Robot
Synopsis
This is a collection of robot stories that he wrote between 1940 and 1976. They're not grouped chronologically, but by theme (and this works really well). The stories, of course, revolve around robots; non-humanoid, immobile, metallic, and humanoid (there's even an android in the last story, but I've already spoiled too much).
Review
Some of these stories are amazing, and you should go pick up this anthology now. My favorites are A Boy's Best Friend, Victory Unintentional, Segregationist, Evidence, Feminine Intuition, and The Bicentennial Man.