Many changes have taken place in pediatric pain management since the undertreatment of children's pain was first reported. Notable advances include an increase in understanding pain during development and improvements in the management of acute pain. Although much more about the safe and effective management of pain in children is now known, this knowledge has not been widely or effectively translated into routine clinical practice. Lack of suitable research on which to firmly establish evidence-based care is likely to have contributed to this situation. A subject of considerable interest recently is the discovery that the experience of pain in early life may lead to long-term consequences. New research findings from laboratory and clinical studies have clearly identified possible mechanisms and provided evidence that long-term behavioral changes can extend far beyond what would be considered the normal period of postinjury recovery. Timing, degree of injury, and administered analgesia and its nature may be important determinants of the long-term outcome of infant pain. Chronic pain, including neuropathic pain, is far more common in children than was thought. The assessment and treatment of this pain and its functional consequences present a considerable unmet challenge. There is a pressing need for further research and clinical development in the management of pain in children.