This book is...fine. The bulk of it, the part focused on the numina and mechanics is good, though it is, of course, old and has been updated in later books to fit more recent mechanics. The organizations are interesting, but there's not much information on how Sorcerers fit in with Mage (except for a nice discussion of the mechanics of having a sorcerer Awaken or be Embraced) and particularly little mention of scientific sorcerers except for one UFO cult, certainly no mention of their use with the Technocracy. The book is good for what it is, but a lot of it has been superseded by more recent books that have done it better.