In 1982, Jebb was commissioned as a military intelligence officer in West Point's Department of Social Sciences and went on to work in the
National Security Agency (NSA). While in the NSA, she was part of the senior faculty as deputy commander of the
704th Military Intelligence Brigade. During 2000–2001, she was U.S. Military Academy Fellow Naval War College, teaching strategy and force planning. During 2006–2007, she was also a visiting fellow at the
Pell Center. She retired from military service and relinquished her position as dean to a newly promoted brigadier general, Shane Reeves, on May 28, 2021. ==Post-military career==