Nuclear reactor physics is the core discipline of nuclear engineering. Nuclear reactors now account for a significant portion of the electrical power generated worldwide, and new power reactors with improved fuel cycles are being developed. At the same time, the past few decades have seen an ever-increasing number of industrial, medical, military, and research applications for nuclear reactors. The second edition of this successful comprehensive textbook and reference on basic and advanced nuclear reactor physics has been completely updated, revised and enlarged to include the latest developments.
Especially for beginning reactor physics classes, go with the Duderstadt book. It's much clearer. For this to be useful, you kind of need to know all of it already. I remember being really annoyed once when a variable was used and never defined (before OR after the equation). We ended up sharing a couple of copies of Duderstadt from the prof and the library in order to understand enough to use the Stacey book.
"Book is hard to read, even for a nuclear engineering student"
Written By: Emerald B. Russo
My professor was so excited when this new book came out. As we started reading it, we realized that the doctor who wrote this book was aiming it at an audience who would already know all of this, never really introducing any new terms or reviewing in any way the new materials to allow the student (who is supposed to be learning it for the first time) to really learn the subject. We ended up switching back to the old book for the remainder of the class. Over all, don't buy unless you already know what you are talking about.