Helms began his career in intelligence by serving in the war-time Office of Strategic Services (OSS). Following the allied victory Helms was stationed in Germany, serving under Allen Dulles and Frank Wisner. In late 1945, President Truman terminated the OSS. Back in Washington, Helms continued similar intelligence work as part of the Strategic Services Unit (SSU), later called the "Office of Special Operations" (OSO). During this period, Helms focused on espionage in central Europe at the start of the Cold War, and took part in the vetting of the German Gehlen spy organization. The OSO was incorporated into the Central Intelligence Agency (CIA) when it was founded in 1947.