As a music educator with over 30 years of experience and who has taught well over five thousand persons the joys of making their own music, I am still having some of my students purchase this small (and inadequate) workbook, but only after having studied all the basics using a book I'll mention in a moment. In other words, if you are starting out, do NOT purchase this book. I have been so discouraged with the current music theory "workbooks" which claim to be "easy" but NEVER explain anything. This book is unorganized, certainly not comprehensive in chord content (and that's important). But, this book does offers a certain value for the average keyboard student who needs a review. I know the reader is now asking, "well, what IS the best book to purchase?" Currently, there is only ONE "non-aligned" (that is, written to be used independently from method books like Bastien or Thompson) theory workbook---but it is dated. I would advise the reader to purchase the "John Brimhall Theory Workbook (Complete)". It's published by Hansen House. This workbook is certainly the best organized I've seen (although it STILL does not explain much, it simple "tells" the reader the facts (so do all the other workbooks). It also---like every other theory book I've used---come with errors: such as having all major chords abbreviated using a capitol "M" after the chord---which has not been used since the 1850s. Also, most music theory workbooks never reveal the "mystery" of what is a "double sharp" or "double flat" (neither does Feldstein OR Brimhall). I have been working on producing a new comprehensive music theory workbook, but don't look for it until 2006. Lastly, a bit of advice: all authors of music theory books "assume" that the reader understands "something" about playing the keyboard. After teaching beginners of all ages for many years, that assumption is false. My best advice? Purchase the Brimhall for basics and then---find a GOOD teacher (and that means not going to the neighbor down the street who gives lessons so they can have some extra money!). Ask questions; find someone who takes time to explain; remember, this is supposed to be more fun than "root canal" (with apologies to my dentist!).