Lack of consensus about pain care has been a persistent challenge since pain was designated the 5th vital sign in 2000. Despite agreement that a better integration of the delivery of medical and mental healthcare in the United States is needed, confusion exists in the context of the relationship between biomedical and biopsychosocial approaches to pain care. When the International Association for the Study of Pain approved a definition of pain in 1979, the intention was to promote the idea that pain was not only a nociceptive phenomenon that could be explained on neurophysiologic basis, but also an emotional experience “associated with actual or potential tissue damage, or described in terms of such damage,” recognizing the need for a universal classification of the human experience of pain. This presentation will explore these topics as well as an in-depth review of the first revision of IASP definition of pain in over 40 years (July 2020), from both a psychologist’s and physician’s perspective.