What was Josh Lyman's official title at the start of the series?

At the start of The West Wing, Josh Lyman’s official title is Deputy Chief of Staff.

Played by Bradley Whitford, Josh serves as President Jed Bartlet’s energetic and politically minded deputy to Chief of Staff Leo McGarry. The series premiere introduces him as one of the administration’s central senior staffers, and much of his work involves congressional negotiations, legislative strategy, political damage control, and advising the president.

Josh is sometimes described more broadly as Bartlet’s chief political adviser, but that is a description of his responsibilities rather than the title used in the show’s staff hierarchy. He is not the National Security Advisor, Press Secretary, or Communications Director: those roles belong to Nancy McNally, C.J. Cregg, and Toby Ziegler respectively.

Josh holds the deputy chief of staff position through the first six seasons. After leaving the White House to manage Matt Santos’s presidential campaign, he eventually returns to government in the series finale as White House Chief of Staff.