Unlike many other books that you probably see for learning Thai, this book presents Thai in a useful, classroom way similar to how you learn French or Spanish in high school. Other books are geared more towards tourists and place importance on being able to speak phrases, but this book works in a much more organized manner and places an importance on learning how to read and write so that you don't have to rely on transliteration systems that ultimately end up being useless. If you're seriously interested in learning Thai from an academic standpoint and not just for tourism, this is the best place to start. Also, be sure that you really learn how to read written Thai before continuing on to the next book in the series, because you'll be really thrown under a bus if you don't. Transliteration still exists when vocabulary is introduced, but disappears afterwards in exercises. I don't know what the third book is like yet, but I assume that if you really don't know how to read Thai by then, you wasted your time.