Addiction Medicine is an immature field but one that is rapidly growing and changing. Research into various aspects of addiction is rapidly advancing. For example, our emerging understanding of the importance of the limbic reward system as the final common neurological pathway in acquiring or manifesting addiction and in the craving and abstinence syndromes both acute and protracted; the continued development of receptor theory; the availability of validated assessment tools and placement criteria; new pharmacological therapies... all of these lead to pressure to make changes in treatment on the grounds of improved clinical understanding. We will be discussing some of these advances as they apply to the assessment and treatment of withdrawal states in particular, and patients seeking addiction treatment in general.