Paralysis of the arm or leg is common after stroke and frequently causes problems with activities of daily living such as walking, dressing or eating. Mirror therapy is a rehabilitation therapy in which a mirror is placed between the arms or legs so that the image of the non-affected limb gives the illusion of normal movement in the affected limb. We found 14 relevant studies involving 567 participants. At the end of treatment, mirror therapy improved movement of the affected limb and the ability to carry out daily activities. Mirror therapy reduced pain after stroke, but only in patients with a complex regional pain syndrome. The beneficial effects on movement were maintained for six months, but not in all study groups. No adverse side effects were reported. Further research is needed with larger studies in natural clinical settings, and with a comparison of mirror therapy with more routine treatments.