It's one of Washington's most important jobs—serving as the president's lawyer. Alumni include Washington legends such as Clark Clifford, Lloyd Cutler, and C. Boyden Gray. At 42, Ruemmler comes to the position with a plethora of experience as a federal prosecutor. She delivered the summation in the trial of Enron executives Kenneth Lay and Jeffrey Skilling. In 2009, after a stint in the Washington office of Latham & Watkins, the Georgetown University Law School grad joined the Obama administration at the Justice Department and then moved over to the White House Counsel's Office in 2010; she became the counsel in 2011 when Robert Bauer left the post. In 2012, Ruemmler had the honor of telling Obama that the Supreme Court had upheld the individual insurance mandate, the central tenet of his health care reform law. And this year, she accompanied him to Boston to provide counsel on the decision to try the Boston Marathon bombing suspect in criminal court rather than as an enemy combatant. She also has had some grim news to deliver. The president's recess appointments were shot down in federal court earlier this year, and an appeal will be tough to win. And then there's the fallout to deal with from Supreme Court decisions on a bevy of cases near and dear to the White House, including same-sex marriage, the Voting Rights Act, and affirmative action. One thing is sure: Ruemmler will be at Obama's side.