Sylvester is the son of a Foreign Service officer, and he grew up overseas, attending junior high school in Norway.
[1] He is a veteran operations official for the CIA and served in several locations overseas, including in the Middle East.
[1] Sylvester rose to the position of Deputy Director for Operations in the summer of 2023, replacing David Marlowe.
[2] In this position, Sylvester is head of the Directorate of Operations, thus being the leader of espionage for the agency.
[2] In February 2024, Sylvester appeared on the CIA's podcast, speaking publicly for the first time,[1][2] discussing the importance of human assets in espionage despite the "proliferation of cyberintelligence.