The High Standard HDM is a semiautomatic pistol equipped with an integral suppressor. Based on the High Standard HD model target pistol, it was adopted by the Office of Strategic Services (OSS) during World War II. OSS head Bill Donovan demonstrated the pistol to President Franklin Roosevelt inside the Oval Office. Because of legal concerns during wartime, full-metal-jacketed .22 LR rounds were developed for this pistol.

It is still found in United States inventories, including that of the CIA, United States Marines, and Special Forces. The weapon was also assigned to the Lockheed U-2 pilots. "The pistol was especially made by High Standard. It was .22 caliber and had an extra long barrel with a silencer on the end."