If you’re trying to read the series chronologically, this actually comes after Prelude to Foundation. I was confused and thought it came at the end of the series, after Foundation and Earth, and now I’m going back and reading Prelude, and I realize I was wrong.

Anyway, this is the fascinating story of how Hari Seldon fought to establish his foundation and to bring psychohistory to fruition in the face of a dying empire. It is sad but poignant, and brilliantly ties in elements from all of Asimov’s related series.

I only wish there was a book that bridged the gap between this and Foundation.

(I just found out that other authors have filled in the gap with Foundation’s Friends and then a whole Second Foundation Trilogy! I can’t imagine it being as good, but I’m going to give it a try.)