Patients with Parkinson's disease (PD) will be trained using a cognitive behavioral group-training-program to reduce stress and augment quality of life. An unspecific group with the same amount and frequency of meetings is used as a control group. For the evaluation of the training effects, scales to assess quality of life, analyses of psychopathological variations as well as neurocognitive tests will be used. Protocol amendment in 1-2017: addition of FU year 3 and year 5.