This is an excellent introductory text on set theory. It provides a fast and thorough coverage of the basics in an economical, if terse, style. If you diligently go through this short 200 page book you will have a solid grasp of set theory that you can immediately use on the job.
I am an IT consultant so, although this book has a much wider audience, I am focusing my review on how this book applies to IT. Because many e-commerce systems are being designed using role-based access controls that are independent of any specific application it is essential that the designers have a thorough understanding of set theory. As such, I think this book is an indispensable quick reference guide for IT security specialists, system architects and QA team members who need to brush op on the subject. These folks design, validate and verify systems that require strong security from within and outside of their organizations. This type of work requires a provably correct design that can only be approached with set theory. Moreover, the testing of the design, as implemented, also requires an understanding of this subject in order to develop a viable test strategy and produce test cases. Given the fact that most IT professionals are not versed in set theory, this book is one of the quickest ways to get up-to-speed.
Among the highlights of this book are: the paradoxes in set theory, which is "must reading" regardless of how you intend to use the knowledge and skills that this book provides, algebra of propositions and logical reasoning.
This book is clearly written, however, the material requires a strong dedication to learning because the subject is complex and dry. No author, regardless of his or her writing skills can change that. If you need to understand set theory and don't know where to begin, this book is one of the best starting points I have come across.