SUMMARY Fibromyalgia is a medically controversial disorder consisting of widespread muscular pain, fatigue and sleep disturbance. There are some similarities to chronic fatigue syndrome and it may have a significant psychological component. Comorbidities such as irritable bowel and restless legs syndromes are common; new diagnostic criteria have recently been formulated to take account of the multiple symptoms. Onset of fibromyalgia may follow physical or mental injury and can have a disruptive effect on normal life. Despite medical ambivalence, courts see fibromyalgia as a life-changing illness and grant substantial damages if a culpable injury is considered to have been the trigger. There is increasing evidence that the perceived pain and other symptoms involve dysfunction in central sensory processing systems. The mainstays of treatment are serotonin- and noradrenaline-boosting antidepressants, GABA analog anticonvulsants and cognitive behavioral therapy with graded exercise, but most patients gain only partial benefit despite their physicians' best endeavors.