237 untreated patients with probable Parkinson's disease could be followed 10 weeks up to 86 months after the first neurological examination. The clinical investigation and the estimation of the severity of the parkinsonian symptoms was done every time according to UPDRS. All patients received cranial computed tomography or MRI of the head, neuropsychological tests, and some of them also SPECT investigation with 123I-Ioflupane (Da TSCAN) or IBZM and/or neurophysiological examinations ( tremor analysis ). The study analysed the appearance, presence and course of the main motor symptoms (bradykinesia, rigidity, tremor, postural instability ) of the Parkinson syndrome, looked for the possible influence upon other motor symptoms, and investigated the presence, course and importance of the non-motor symptoms in the early stages of the disease. There were also examinated the diagnosis algorithmus of the Parkinson's disease in the early stages, the estimation of the stages duration, and the clinical criteria of the therapy initiation.