Fatigue is a recognized problem in Parkinson's disease and other clinical conditions. We characterized this symptom in 19 patients and 19 age- and sex-matched controls, using the Multidimensional Fatigue Inventory (MFI) and the Geriatric Depression Scale. Fatigue may be an independent symptom in Parkinson's disease, frequently associated with depression. Our analysis showed the usefulness of the MFI in discriminating between different dimensions of fatigue for a better therapeutic approach.