Pain is a common reason for individuals to seek medical care. In 2003, three of the 20 most frequently mentioned reasons for outpatient department visits in the United States were related to stomach, head, or back pain.1 Similarly, in a 1998 study, 21.5% of persons in a multinational sample across Asia, Africa, Europe, and the Americas reported pain most of the time during the previous 6 months.2 In a study of more than 46000 European and Israeli persons, the prevalence of chronic pain ranged from 12% to 30%, with a weighted average of 19%.3 In the United States, pain is often suboptimally treated in persons of all ages and a wide variety of conditions.4–12 Important clinical, human, and economic consequences of this shortcoming include altered immune-system functioning, diminished ability to function, increased risk of chronic pain, needless suffering, and higher healthcare costs.13–22 In the United States, 2002 costs of lost productive time caused by pain have been estimated at $61.2 billion.23 A sample of individuals with neuropathic pain disorders incurred charges of more than$17000 during calendar year 2000 compared to approximately $5715 in a matched control group without neuropathic pain.24 An analysis of symptomatic diabetic peripheral neuropathy and its associated complications found that 2001 costs were approximately$237 million.25