Tamar D. Black, PhD, is an educational and developmental psychologist in Melbourne, Victoria, Australia. She runs a private practice working with children, adolescents, young adults, and parents. Tamar has extensive experience providing clinical supervision to early career and highly experienced psychologists. She also provides training in acceptance and commitment therapy (ACT) to clinicians and teachers. She is author of the professional guide, ACT for Treating Children.

Foreword writer Russ Harris is an internationally acclaimed ACT trainer; and author of the best-selling ACT-based self-help book, The Happiness Trap, which has sold more than one million copies and been published in thirty languages.