Novel therapies with the ability to delay disease progression are a gap in the care of people living with Parkinson disease (PD) today. Clinical outcomes assessments (COAs) that are sensitive to the earliest clinical changes in PD are deemed essential for a successful therapeutic development. To understand the current landscape of COAs use in clinical trials in PD and define priorities for future research in the field, a stakeholder roundtable meeting was held in November 2022. The current paper 1) proposes the collaborative development of patient-centric COAs that can adequately document the effectiveness of disease modification therapies in PD based on key priorities identified during this initial meeting, 2) summarizes the progress made in the subsequent 12 months, and 3) presents the deliverables expected in the near future. Key priorities include 1) the development of a consensus conceptual model of early PD experiences, 2) the adaptation of existing patient-reported outcomes (PROs), 3) the investigation of the role of observer-reported outcomes in addition to 4) enabling diversity in PD research and advocacy, 5) fostering data sharing, and 6) reaching consensus on a biological staging system for PD to drive the development of appropriate PROs for biologically defined populations.