The historical basis of restless legs syndrome / K. Ray Chaudhuri and Sharon Muzerengi -- What causes restless legs syndrome? / Luigi Ferini-Strambi -- Epidemiology -- Quality of life / K. Ray Chaudhuri and Sharon Muzerengi -- Differential diagnosis / K. Ray Chaudhuri, David Rye, and Sharon Muzerengi -- Secondary RLS / William Ondo -- Treatment of restless legs syndrome and periodic limb movement disorder / K. Ray Chaudhuri and Sharon Muzerengi -- Illustrative case reports / K. Ray Chaudhuri, Sharon Muzerengi, and William Ondo -- Future directions / D. Rye and K. Ray Chaudhuri.