A collection of his science fiction stories, one fantasy one, and several poems.
A sampler. There are several stories from different universes of his: Time Patrol, Operation Chaos, several of the Technic History (one apiece of Nicholas van Rijn, David Falkayn, and Dominic Flandry). Also stand-alones. Some are puzzle stories -- sometimes with tragic implications.
Uneven in quality, I think not so good as the other series. "Sam Hall", however, is one of his best and it has many other good ones.