This is an excellent collection of stories, in fact one of the best I've ever read. Each author, and there are about 15 of the best, introduce each story by telling how they came up with the idea for the story they selected, why it is their own personal favorite and what they were thinking about when they wrote it. "Writer's choice" literally means that the editor, Rust Hills, of Iowa Workshop fame, picked probably his favorite authors and let them "choose" which story they would like to include and asked them to explain why.
This book is out of print and very hard to find but I highly reccomend buying one if you can find it. My copy is very old and worn, but I reread it often. Richard Yates, Donald Barthelme, James Purdy, Evan S. Connell and Truman Capote are all present here and at the top of their game.