The Definition of Done (DoD) is a shared understanding of what it means for work to be considered complete. It is typically defined by the project sponsor and project team in collaboration. The DoD outlines the criteria that must be met for user stories, features, or tasks to be considered done, ensuring alignment between stakeholders and the development team. While the product owner, Scrum master, and stakeholders may influence the criteria, the final agreement on what constitutes "done" is determined by the project team and sponsor.