An approval policy is used to govern whether a service catalog user needs approval from someone in your organization to provision items in your environment.
A tenant administrator or approval administrator can create approval policies. The policies can be for pre-provisioning or post-provisioning. If a pre-approval is configured, then the request must be approved before the request is provisioned. If it is a post-approval, the request must be approved before the provisioned item is released to the requesting user.
The policies are applied to items in an entitlement. You can apply them to services, catalog items, catalog item components, or actions that require an approver to approve or reject a provisioning request.
When a service catalog user requests an item that includes one or more approval policies, the approval request is sent to the approvers. If approved, the request moves forward. If rejected, the request is canceled and the service catalog user is notified regarding the rejection.