Elizabeth Coss MacDonough is an American lawyer who has served as the Parliamentarian of the United States Senate since 2012, making her the first woman to hold the position. In this role, MacDonough guided the Senate through significant procedural events, including the first and second impeachment trials of Donald Trump. Her career began in 1990 as a legislative reference assistant in the Senate library, followed by a role as assistant morning business editor to the Congressional Record.