The study is a longitudinal, multi-center study to assess progression of \[18F\] AV-133 imaging in Prodromal PD participants. Participants will be followed for up to 24 months. Approximately 100 Prodromal participants will be recruited from up to 10 sites. Participants will be comprehensively assessed at baseline and follow up. Participants will undergo imaging assessments with \[18F\] AV-133 and clinical (motor, neuropsychiatric, cognitive and imaging and biomarker) assessments (conducted under the PPMI Clinical protocol).