A RACI matrix is a document that clarifies those questions: which individuals or groups are responsible for a project’s successful completion? Which roles will they play throughout the project? RACI stands for the different responsibility types: Responsible, Accountable, Consulted, and Informed.
Another commonly used variant is RASIC assignment. In addition to the points mentioned above, the “S” stands for ‘Support’ and thus refers to persons (e.g., subject matter experts) or resources that support those “responsible” in carrying out the task.