Katherine Stone was the former Overseer of Vault 11.
During her time as Overseer, she instituted Overseer Order 745, stating that any future Overseer will no longer be chosen by election but rather by random from a computer. This decision most likely brought the downfall of Vault 11. Prior to her election, members of the Justice Bloc, a powerful voting group, threatened to nominate her husband, Nathan Stone, for Overseer unless she performed sexual favors for them. She complied, but the Bloc still nominated her husband. She then took it upon herself to kill as many members of the Justice Bloc as she could, almost guaranteeing her election. Riots broke out after she issued Overseer Order 745, which eventually led to the fall of Vault 11.
Katherine Stone is mentioned only in Fallout: New Vegas.