I love the books of Andre Norton - with very few exceptions, they are so consistently good - well-written characters, intricate plotting, and when she's writing of something out of the common way it feels alien. She has strong, no-nonsense women characters and people act like people do, not like literary characters do.
This one is consistent in quality with the rest. Although it is a sequel to Crystal Gryphon, it can be read as a standalone book (I haven't read Crystal Gryphon yet). Kerovan thinks he is unworthy of the Lady Joisan because of his mixed blood and physical "imperfections", and leaves; Joisan has little reason to stay and much to go after him. She follows him into the Wastes, where assorted trouble finds each of them, and where they must find each other.
If you like Norton you'll love this; if you haven't tried her you should still enjoy it anyway. Can recommend.