Pain is described by the patient mostly in terms such as stabbing, burning, tearing, squeezing, etc. Acute pain is accompanied by a stress response consisting of increase in blood pressure, tachycardia, pupillary dilatation, and high plasma cortisol levels. This may be accompanied by local muscle contraction. Four broad categories of pain are generally nociception, pain perception, pain behaviours. Chronic pain affects 20% of the European population and is commoner in women, older people, and with relative deprivation. Its management in the community remains generally unsatisfactory, partly because of lack of evidence for effective interventions. Good epidemiological research on chronic pain provides important information on prevalence and factors associated with its onset and persistence. Improving our understanding of associated factors will inform our clinical management, limiting severity, and minimizing disability.