The Owner of the data is responsible for making decisions about the data, establishing control mechanisms, and determining data classification levels. They are accountable for ensuring that the data is properly protected and used in compliance with legal and organizational requirements. The Processor is responsible for processing data on behalf of the Controller as per their instructions. The Custodian (also known as the Steward) is responsible for maintaining and protecting the data assets on a day-to-day basis. The Controller determines the purposes for which and the means by which personal data is processed but may not own the data or the process.