National Association of Letter Carriers: Since 1993, the National Association of Letter Carriers has held its Stamp Out Hunger Food Drive, in which letter carriers gather food donations while making their rounds. And for the event’s 25th anniversary, the union decided there was only one way to celebrate: with personalized stamps.

American Philatelic Society: The American Philatelic Society has been bringing stamp collectors together since its first annual convention in September 1886. Today, the association hosts a series of events for philatelists, like its StampShow and AmeriStamp Expo, to continue this mission.

National Stamp Dealers Association: Philatelists need someone to buy their stamps from, and that’s where the National Stamp Dealers Association comes in. As the largest organization of its kind in the world, NSDA supports members by setting standards for ethical dealing, helping dealers grow their businesses, and providing tips and strategies for successful stamp selling.

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