Deep brain stimulation (DBS) has gained increasing attention as a therapy for movement disorders. Neuropsychological alterations can accompany the disease evolution and medical therapy of PD. Also, interfering abruptly with the biological balance by means of a surgical intervention into complex circuits with motor but also cognitive and limbic functions, could potentially cause severe problems. Because cognitive or emotional impairments may have an even stronger impact on quality of life, than motor symptoms, care must be taken to perform surgery in the safest possible way to exclude adverse effects in these domains. Detailed neuropsychological evaluations may become helpful to further understand the mechanisms underlying some aspects of the clinical pictures both pre- and postoperatively and to define risk populations, that should be excluded from this intervention.