We recommend that the Centers for Medicare & Medicaid Services update applicable Medicare requirements to clarify which types of professional and public education overhead costs are unallowable (e.g., clarify whether the costs of meals provided to non-OPO employees for professional education and the costs of tickets to entertainment events purchased for the purpose of public education are unallowable), which could have saved Medicare an estimated $664,295 for professional and public education overhead costs during our audit period.