The purpose of this research study is to see if subjects with Parkinson's disease who are experiencing motor fluctuations ("on" and "off" states) and dyskinesias (involuntary excessive movements) would benefit from a higher dose of Requip as compared to the maximum FDA approved dose of dopamine agonist drugs (including Requip, Mirapex, and Permax). Requip as used in this study is investigational, which means it has not been approved by the US Food and Drug Administration (FDA) at this dose level.

Inclusion Criteria:

• Patients must give written informed consent prior to any specific study procedures.
• Males or females; females of childbearing age who are not currently pregnant must agree to use a medically accepted method of contraception throughout the study.
• Age greater than or equal to 25 years.
• Patients must be on a maximum dose of dopamine agonist drug (pergolide 4mg/day, pramipexole 4.5 mg/day or ropinirole 24mg/day).
• Stable dose of all medications for 4 weeks.

Exclusion Criteria:

• Current hallucinations.
• History of disabling hallucinations or hallucinations in past requiring treatment.
• Troublesome edema (swelling).
• Unstable depression.
• Female who is pregnant or lactating.
• Use of an investigational drug with in the last 30 days.
• Other inclusion or exclusion criteria to be evaluated by the physician.