Kitty Harris (died 6 October 1966) was a Canadian-born Soviet secret agent and "long-time special courier of the OGPU-NKVD foreign intelligence during the 1930s and 1940s.
"[1] Although mentioned by name in Walter Krivitsky’s book I was Stalin’s agent, Harris was identified only in 2001 when her code name "Ada" or "Aida" was found in declassified files from the Venona project.
This was a counterintelligence program initiated by the United States Army's Signal Intelligence Service (later the National Security Agency) that ran from February 1, 1943 until October 1, 1980.
Catherine (the earliest spelling is Katherine) Harris was born to a poor Polish Jewish family, probably in London, Ontario, sometime between 1893 and 1902.
She joined the Industrial Workers of the World (IWW or "Wobblies") union and was a leader of the 1919 Winnipeg General Strike.
A year later, she visited Shanghai, China, with Browder: there, he became secretary of the Pan-Pacific Trade Union Secretariat, (part of the Comintern) and she became a courier.
When France fell to the Nazis in 1940, she escaped to Moscow, where she worked in the NKGB foreign intelligence reserve.