Spy swaps have precedence in East-West relations, especially during the Cold War. Downed U-2 pilot Gary Powers and Rudolf Abel are just two famous examples.
KGB Colonel Rudolf Abel, arrested in the United States in the late 1950s, was freed in 1962 in exchange for Gary Powers, pilot of a U.S. U-2 spy plane that was shot down over the Soviet Union in 1960. The swap took place on the Glienicke Bridge between West Berlin and Potsdam in East Germany.
Britain struck a deal with Moscow in 1969 to release Peter and Helen Kroger from prison early in exchange for the freedom of lecturer Gerald Brooke, who was jailed for espionage in the Soviet Union. The Krogers were part of a group of five agents arrested for passing on secrets from the Royal Navy's underwater warfare establishment at Portland, southern England.
Guenter Guillaume, an agent for East Germany's Stasi who was unmasked among the closest aides of West German Chancellor Willy Brandt, was exchanged for captured Western agents. He had served eight years of a 13-year jail sentence before he was handed over to East Germany in 1981.
The Guillaume and Powers/Abel exchanges were handled by East German spy-swap lawyer Wolfgang Vogel. He also negotiated the 1986 exchange at the Glienicke Bridge of Soviet Jewish dissident Anatoly Shcharansky (now Natan Sharansky) for Communist spies jailed in the West. In all, Vogel brokered the exchange of more than 150 spies.