Until the early 1970s, anxiety was considered the major psychological concomitant of acute and chronic pain, stemming from Sigmund Freud's initial formulations postulating an intimate relationship between pain and anxiety. The formulation that began to emerge in the 1970s was to differentiate between anxiety, as the major emotional concomitant of acute pain, and depression. as more importantly associated with chronic pain. This dichotomy has been borne out and proven clinically useful. However, the decades-long, almost total neglect of anxiety as a psychological condition of significance to patients with chronic pain was unfortunate. In recent years, researchers have begun to correct this oversight.