A middling Culture novel, which is to say a great sci-fi novel. You have many of the standard Culture tropes, however the quality and inventiveness of the details is such that even a partial re-tread is still a delight to read. The story itself is somewhat meandering, and follows a variety of different entities at various levels of technology, intellect, and reality. Some of these story threads threads taper out and some don't really connect to the others, so it is more of a slice of life novel rather than one that comes to a sharp point. There's a little twist at the end, but it's nothing like, say, _The Use of Weapons_.