More than 100,000 US Veterans living with Parkinson's disease (PD) currently receive PD-related care and services from the VA. In addition to well-defined motor complications, PD is also characterized by progressive cognitive decline, predominantly executive function (EF) deficits. PD-related cognitive decline is clinically significant because it leads to long-term functional impairment and diminished quality of life (QoL). Currently, 20-55% of PD patients have mild cognitive impairment (PD-MCI) and up to 80% will develop dementia (PD- D). Limited treatment options for PD-MCI and PD-D and the possible need to tailor treatments to Veterans makes cognitive rehabilitation an important VA research topic. Computerized cognitive training (CCT) shows promise as an effective cognitive rehabilitation approach for geriatric patient populations with cognitive decline. In PD, emerging evidence reveals cognitive training improves cognition immediately following training with moderate to large effect sizes on measures of EF. However most studies only included PD patients with normal cognition (PD-N); only one assessed at-home CCT (with PD-N participants). Thus, no PD studies have assessed the ability of at-home, CCT programs to improve cognition in PD patients with mild executive dysfunction (PD-MCI-EF). Moreover, there is paucity in understanding if CCT-induced improvements transfer to daily activities. This SPiRE seeks to address these gaps by conducting a pilot randomized controlled trial (RCT) to examine the feasibility of conducting an 8-week at-home cognitive training program using an existing web-based EF CCT program with or without training in prospective implementation intentions strategies (PRIIS) in Veterans with PD-MCI-EF. Implementation intention strategies are effective in Alzheimer's disease and it shows promise in PD patients. PRIIS that builds on cognitive skills trained in CCT and incorporates prospective memory training that focuses on patient-centered self-management strategies may boost far transfer effects of CCT. The central hypothesis is that CCT+PRIIS, compared to CCT+PRIIS control or CCT control+ PRIIS control, will lead to greater improvements in cognitive performance and every day function. Participants will be randomized to either CCT (four 30min sessions/week) plus PRIIS (implementation intentions), CCT plus PRIIS control (verbal rehearsal of intentions) or CCT control (entertaining computer games) plus PRIIS control. The hypothesis is that CCT+PRIIS program will be feasible as indicated by participant protocol completion rates. Additional information on participants' perception (i.e. enjoyment, mental stimulation) of the CCT and PRIIS programs will be qualitatively assessed. Participants will also complete a standardized neurocognitive battery at baseline, endpoint (immediately after 8-week intervention) and at a 1-month follow-up. The hypothesis is that CCT+PRIIS, compared to other groups, will improve performance on untrained c...