Cognitive impairment is common among non-demented individuals with Parkinson disease (PD) and is a significant source of disability and reduced quality of life. Unfortunately, there are no successful interventions to address these impairments. Prospective memory impairment is a particularly functionally- and clinically-relevant problem in PD. The investigator's project will determine if a targeted intervention strategy improves PD participants' prospective memory. The investigator's goal is to improve PD patients' everyday prospective memory so they can successfully perform desired activities and roles.