Eye movements are performed in order to either focus the gaze onto anew interesting object or to stabilize the viewed object in the fovea. As every type of eye movement has its own anatomical substrate, it is often possible to localize an eye movement disorder to aspecific brain region or to make adiagnosis of asystemic disease in an appropriate clinical setting. Thus, in many patients the assessment of eye movements can effectively help in the diagnosis and appropriate treatment can be initiated in a timely manner.