Abstract-We examined the impact of multidisciplinary clinical management of the Parkinson's Disease Research, Education, and Clinical Center program on Parkinson's disease progression. Initial and follow-up scores on the Part III Motor Examination subscale of the Unified Parkinson's Disease Rating Scale (UPDRS) were examined. Overall, 37 (75.5%) of the 49 patients demonstrated stable or improved UPDRS motor scores at 1-to 3-year follow-up; in the 1-year group (n = 28), 22 patients (78.6%) improved, while 6 (21.4%) worsened. In the 2-year group (n = 15), 10 (66.7%) improved, while 5 (33.3%) worsened. In the 3-year group (n = 6), 5 (83.3%) improved, while 1 (16.7%) worsened. Multidisciplinary interventions included neurology (95.9% of patients), physiatry (93.9%), nursing (87.8%), psychology (42.9%), medication changes (59.2% increases, 18.4% decreases), rehabilitation therapies (physical, occupational, speech-language, 67.3%), functional diagnostic testing (18.4%), support group (16.3%), home exercise instruction (85.7%), and disease and wellness education (81.6%). Improved and worsened patients did not significantly differ on the individual program components. Clinical implications and study limitations are discussed.