Since L-dopa in combination with a decarboxylase inhibitor is currently the most effective therapy available for treatment of Parkinson's disease, the authors compare the actual causes of death in a large series of treated Parkinson patients with a normal population and with previous studies. This investigation shows that the mortality of correctly treated Parkinson patients lies within the range of the expected mortality of a group of a normal population comparable in age and sex. The risk of death for a Parkinson patient is therefore no longer higher than for the normal population.