While you can certainly finish the book in 30 days, you'll most likely forget the vocabularies in at least half of the chapters by the time you are done. The quiz in each chapter is useful. The diagnostic test at the beginning of the book can crush your self-esteem - which is to be redeemed after reading the book. "30 days" in the title is misleading, because readers probably need to go through the chapters again and again to make sure they truly remember the words. So make it "45-50 days to a more powerful vocabulary"!

Furthermore, believe it or not: it is not a bad cram book if you have less than 3 months to study for SAT or GRE! I find vocabulary builders (such as this title) much better study tools for SAT or GRE than conventional exam preparation guides like Princeton Review or Barron's - at least for the verbal section.

While this book is very helpful in building a more powerful vocabulary, a more appropriate title would be "45 days to a more powerful vocabulary in just 60 minutes a day!" Some lessons must be repeated if you want to really know some of the words. There are no really ground breaking vocabulary memorization techniques in this book either. However, it does a great job of organizing certain vocabulary terms. If you can spare an hour a day for 45 days, this books can be a great help!

This book is an excellent resource for anyone hoping to expand his or her vocabulary. I suppose, as the others below me have said, that the title of this classic book is a bit misleading. Yes, it's true-- you can't learn over two hundred words in "30 days." But whether you can or not does not diminish the fact that this book really does succeed in its aims, and that is to help expand your knowledge and use of words. This book helped fill in the gaps in my own vocabulary, and for that I will be forever grateful to it. I can't recommend it enough.