This application is for the continuation of a NET PD clinical site at the University of Southern California. NET PD was designed to enroll patients in a series of pilot studies and clinical trials of new agents for the treatment of Parkinson's disease. The role of the clinical sites is to identify, screen, enroll, treat, and follow patients in these rials;to report data in a timely manner to the data coordinating center and to report adverse effects among enrolled patients. Currently, NET PD is conducting the LS-1 study, a multi-center, double-blind, phase III clinical trial designed to determine whether or not creatine is more effective than placebo in slowing the clinical decline in PD patients with early, treated PD. Enrollment began in 2007 and was completed on 5-28-10. All patients will be on treatment and followed for a minimum 5 years or until the end of the study. Additional exploratory trials in Parkinson's disease will be developed and conducted utilizing potential neuroprotective agents or combinations of agents over the next 5-year period as determined by the NET-PD study group and NINDS. The University of Southern California has completed 9 years of the LS-1 NET-PD study. The first subject enrolled into the LSI study on 4/30/07. A total of 55 subjects have been enrolled. Of the total enrolled, 3 have been lost to follow up, 3 have expired and the remaining 49 are active. The conduct of the study has been uneventful. Both Males and females from diverse ethnic and racial groups have been enrolled. Subjects are followed according to the protocol and in keeping with good clinical practices. Data is reported in a timely manner to the coordinating center. It is anticipated that future timelines and protocol expectations will be met on schedule.