Alfonso Cuaron directed Harry Potter and the Prisoner of Azkaban. I've been under the impression that he was only ever meant to direct PoA. Can't remember (if I ever knew it) who's directing Goblet of Fire though.
Funnily enough, I quite liked Cuaron's PoA, it was (as I've already mentioned on this thread) Chris Columbus's "Home Alone" clones Harry Potter and Philosopher's Stone & Harry Potter and The Chamber of Secrets that bored me to death.
Edit: I see Purity has already supplied the answer...