The Organ Procurement and Transplantation Network (OPTN) Deceased Donor Potential Study, funded by the Health Resources and Services Administration, characterized the current pool of potential deceased donors and estimated changes through 2020. The goal was to inform policy development and suggest practice changes designed to increase the number of donors and organ transplants. Donor estimates used filtering methodologies applied to datasets from the OPTN, the National Center for Health Statistics, and the Agency for Healthcare Research and Quality and used these estimates with the number of actual donors to estimate the potential donor pool through 2020. Projected growth of the donor pool was 0.5% per year through 2020. Potential donor estimates suggested unrealized donor potential across all demographic groups, with the most significant unrealized potential (70%) in the 50–75-year-old age group and potential Donation after Circulatory Death (DCD) donors. Actual transplants that may be realized from potential donors in these categories are constrained by confounding medical comorbidities not identified in administrative databases and by limiting utilization practices for organs from DCD donors. Policy, regulatory, and practice changes encouraging organ procurement and transplantation of a broader population of potential donors may be required to increase transplant numbers in the United States.