National Taiwan University, Taipei First Girls' High School
Isabelle Cheng (Born September 17, 1970), also known as Cheng Nian-Tzu (程念慈), is an intelligence agent for the National Security Bureau of Taiwan.
Cheng graduated from Taipei First Girls' High School and later National Taiwan University, with a bachelor degree in Political Science in 1993. She came to public attention when her relationship with Donald Keyser, an official of the United States Department of State, became part of criminal charges against Keyser — in 2005, Keyser pleaded guilty to lying about the relationship, and to unauthorized possession of secret documents. Keyser has not been charged with espionage, however. While in the United States, Cheng was operating from the Taipei Economic Cultural and Representative Office in Washington, but has since been called back to Taiwan. She is currently working toward her PhD at an undisclosed university outside of Taiwan.