The VA/DoD published the first Clinical Practice Guideline for management of opioid therapy for chronic pain in 2003. This original publication was intended to improve pain management, quality of life, and quality of care for veterans. The focus of the guideline has been to provide education and guidance to primary care clinicians, researchers and other health professionals as they encounter patients with persistent pain and its complications. This book aims to update the evidence base of the 2003 Guideline. It is focused, as was the original CPG, on chronic opioid therapy (opioid therapy for more than one month). It is directed to the clinician who is interested in knowing more about this approach to the management of chronic pain.