Our son just turned 2 but has been showing signs of being ready to potty train for some time. We haven't pushed it at all, but after ordering this book for him, he's decided to start using his potty. At first he'd only sit on it with the lid down and his clothes on. Then with the potty lid up, and last night, he actually used his potty!
While reading the book: We have developed a little game of looking for Henry's (the character in the book) diaper on each page of the book, which he really enjoys. We also laugh and clap for Henry when Henry uses his potty. This books is very cute, and the rhyming text grasped our sons attention from the very beginning
Beware though, if you get to read it as often as we do... you may find yourself repeating it throughout the day!
Considering my sons complete defiance against the potty before we got this book and a potty seat for him (we originally had bought a toddler size toilet seat which he hated), and his total acceptance and excitment about using the potty now, I would be inclined to say that this book will help nearly ANY little boy with potty training!