ITIL also utilizes the RACI model as a generic tool for reviewing and assigning four key roles to any important task or activity. Whereas role assignments are often well-defined within functions, the RACI model holds particular value for ensuring that roles are appropriately filled or covered within processes.

• Those in the R = RESPONSIBLE role for a given activity are charged with actually executing or performing the activity or task.
• The single entity in the A = ACCOUNTABLE role owns the task or activity and must answer for its outcomes. Only one party can be accountable for a given task/activity.
• Those in the C = CONSULTED role review and provide advice and authorization around the task or activity.
•  Those in the I = INFORMED role receive updates as the task or activity progresses.

**Source by wikipedia**

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