Henry Dunay was born in Jersey City, New Jersey in 1935. At 14, he started his career with an apprenticeship in New York City that lasted seven years. In 1965,  Henry Dunay Designs was launched and immediately won the De Beers Diamonds International Award, the first of his many jewelry design awards. Henry Dunay Designs has become internationally known for its wide range of trend-setting designs. Each piece of jewelry bearing the signature "HENRY DUNAY" is part of a collection that is famous for its hand-engraved textures applied to gold surfaces, use of pavé diamonds and artistically themed jewelry. Among his best known collections are Faceted, Sabi and Diamond, Platinum and Gold, Praslin and Cynnabar. Dunay was also the president and founding member of the American Jewelry Design Council. In 1992, at the Presidential Inaugural Ball, Hillary Clinton wore a Henry Dunay ring set with the yellow Kahn Diamond, found in her home state of Arkansas.

In 2009, Dunay declared bankruptcy and the jewelry house went through an unstable period resulting in the name Henry Dunay Designs being sold at auction. Dunay now works under the name H.D.D. making custom pieces in New York City.