This book describes a simple, evidence-based, yet revolutionary design of the modern behavioral health clinic that fully integrates addiction and mental health diagnoses. This design, called the 2 x 4 model, will eliminate the silos that now pervasively exist between mental health and addiction treatment and expertise in the US. It can serve as a new backbone for a modernized behavioral healthcare system and holds considerable potential in facilitating a woefully needed renaissance in behavioral health in the US.