I haven't read this book, but the summary to me suggest that selective mutism is a choice. It is not. It is an anxiety disorder. Trust me, my son wanted to speak in school, but froze up at every opportunity. My son did not begin speaking in school until the 4th grade and did not speak freely until 5th grade. With the help of medication, therapy, and age, he is doing very well. He is medication free now. He is now in the 7th grade and is the one teachers can't keep quiet. From my experience I don't think this book would have helped. Maybe it would for others.