by E.K. ZSIGMOND, M.D. Department of Anesthesiology University of Illinois Chicago U.S.A. It is, indeed, a distinct honor and privilege to be invited by the authors to write a preface to this monumental monograph, Regional Opioid Analgesia. Regional Opioid Analgesia is a colossal undertaking by Drs. De Castro, Meynadier and Zenz shortly after the introduction of this revolutionary approach to pain relief which opened a new epoch in analgesiology...