Parkinson's disease (PD) is a common progressive neurodegenerative disorder. Dopamine replacement therapy considerably reduces motor handicap. Although levodopa continues as the gold standard for efficacy, its chronic use is associated with potentially disabling motor complications. Strategies to treat levodopa-related motor complications are only partially effective. Best results are currently achieved with invasive strategies via subcutaneous (s.c.) or intraduodenal delivery of apomorphine or levodopa, or deep brain stimulation of the subthalamic nucleus. This presentation will develop the current treatment principles for PD: (1) L-dopa does not accelerate disease progression, (2) no treatment modality exerts neuroprotective effects, (3) L-dopa is more effective than dopamine agonists in alleviating motor symptoms and improving the activities of daily living (ADL) score, in parkinsonian patients, (4) Treatment with dopamine agonist is associated with fewer motor complications than L-dopa. (5) Dopamine agonist therapy is associated with more frequent adverse events than L-dopa therapy, such as hallucinations and somnolence. There is no evidence of a long-term benefit with initial dopamine agonist therapy.