Use of opioids in pain medicine is a rapidly expanding speciality especially since pain pharmacotherapy as a continuum of care is an essential asset in pain medicine. The book has been conceived to fill the void for a comprehensive review of the theoretical knowledge and scope of opioid pharmacotherapy in pain medicine. While the information provided is obtainable in other major text already in print, the present format style plus the illustrations will make easy reading and fast accessibility of information on opioids available. Information provided is based on clinical practice rather than pure experimental data giving the clinician something at hand, which is useful in daily practice. Wherever required, the mechanisms of action of pain pharmacotherapy are described in detail and references are provided to give the reader further sources for additional information.