Parkinson's disease is associated with pathological oscillatory activity in a wide-range cerebral network of sensory and motor areas. A number of studies identified 5 Hz, 10 Hz and 20 Hz as predominant frequencies of oscillatory activity in this cerebral oscillatory network. Clinical evidence for the importance of the pathological oscillatory activity derives from studies showing modulation of motor deficits and cognitive performance during external stimulation of patients with Parkinson's disease at 5 Hz, 10 Hz and 20 Hz. Furthermore, high-frequency stimulation in the subthalamic nucleus successfully alleviates all cardinal motor deficits in Parkinson's disease probably by suppression of 5 Hz, 10 Hz and 20 Hz activity. However, the specific role of each of these frequencies so far remains unclear. The present commentary summarizes the current pathophysiological concepts of pathological oscillatory activity in Parkinson's disease and highlights the new ideas of modulatory intervention.