While I enjoyed this book, it was not at all what I expected. It is sci-fi, because it is set on a different world. And there are 4 different races. But while there is exploration and discussion of what makes the races different, it really is a book about relationships, misconceptions and how to get along with people not the same as you. I was hoping for a little more of the techie stuff - time travel, harder science, action, etc.