If a review requires your approval, go to the Appraisals page. Find the reviewee in question and click the Results button for that person.

If your approval is required, you will see a giant box at the top of the screen with an Approve button.

When you click the Approve button, a confirmation page will pop up. Be sure to click Approve if you are sure you'd like to allow sharing.

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How do I know if an appraisal requires my approval?