Juggler of Worlds by Larry Niven
My rating: 4 of 5 stars
Great book — I’ve got to read more of this series. It’s part of the "Ringworld" universe, but doesn’t deal with that story line directly. It’s a bit of a side-story dealing with, well, the dealings of the Puppeteer race and their dealings with humankind before the Ringworld was found. Great writing, great characters.