Throughout the history of mental health practice, conflicting and irreconcilable theories have caused confusion about how disorders form, what they look like, and how they should be assessed and treated. But thanks to dramatic scientific advances in recent years, these patchwork theories can now be replaced by a unified, science-based, biopsychosocial framework for behavioral healthcare. This book presents the essential scientific and ethical foundations of the biopsychosocial framework and then applies it across the treatment process, from intake through outcome assessment. In doing so, the book provides a critical basis for the increasingly integrated healthcare systems of the 21st century.