What is an Authorization to Operate (ATO) and who issues it?

• A. A formal risk assessment outcome reviewed by the security team.
• B. A temporary approval to test new controls by the system owner.
• C. An external certification required for system import/export.
• D. A formal approval by the Authorizing Official to operate the system.

Answer: (D)

An Authorization to Operate is a formal approval to operate a system in its approved environment, given after security controls are implemented, assessed, and the residual risk is accepted. It designates that the system, within its defined boundary, is authorized to run in production and carry out its designated processing. The person who issues this approval is the Authorizing Official (or Designated Approving Official), the official who has the authority to accept risk on behalf of the organization. This decision often comes with conditions and a plan for continuous monitoring to ensure ongoing risk remains acceptable. It’s not simply the outcome of a risk assessment, not a temporary testing permit, and not an external certification for import/export.