Adult Signature is a new extra service that will provide a method for customers to obtain a signature (upon delivery) from an adult recipient who is 21 years of age or older. This new extra service will be available beginning June 5, 2011, to commercial and online customers who use Express Mail®, Priority Mail® (including Critical Mail), Parcel Select® barcoded nonpresort, and Parcel Select Regional Ground services. The standards will be incorporated into the July online DMM® update. Adult Signature service has two options: Adult Signature Required - requires the signature of someone who is 21 years of age or older at the recipient's address. Adult Signature Restricted Delivery - requires the signature of a specific addressee (or authorized agent), who must be 21 years of age or older. See the complete details on the Adult Signature Service final rule Federal Register, which was posted today on the Postal Explorer® website.