Barring any unanticipated Republican defections, House Ways and Means Committee Chairman Paul Ryan of Wisconsin will be elected Speaker of the House of Representatives tomorrow. But he won’t be the only person on the Hill getting a new job because of the congressional leadership shakeup. A slew of Washington’s top staffers and political professionals will win new jobs as Ryan assembles a staff for the Speaker’s office. In fact, he has reportedly already asked former congressional aide Dave Hoppe, who has loads of Capitol Hill experience, to serve as his chief of staff. Although the public outside Washington generally will not notice them, Ryan’s staffers for his Speaker’s office, along with their colleagues in other leadership offices, will become major players directing their party, the Congress, and the country.

Congressional leaders, like the Speaker or the House and Senate Majority and Minority Leaders, are provided with funds to hire two sets of staff: one to oversee responsibilities relating to their duties simply as Members of Congress and one to assist with their duties as leaders of the institution. The former set is typically referred to as the “personal staff” for the “personal office”—these are the staff members citizens communicate with when they contact their elected officials. The latter set is generally known as “leadership staff”. The public has little, if any, contact with these staffers.

Many of the leadership staff have similar roles to those in the personal office. At the top is the chief of staff, who directs the activities of all the aides working to implement the leader’s agenda. Although most rank-and-file Representatives do not have deputy chiefs of staff, congressional leaders typically have at least one deputy chief and maybe multiple. Like personal offices, they also have a number of staff to develop policy positions and to handle communications. Since leaders have many demands upon their time, they also have typically have one or more staffers dedicated to managing their schedules.

In addition to staff with responsibilities similar to those in the personal offices, leadership offices have a number of aides whose duties are not parallel to any in personal offices. For instance, leaders will typically have a “director of Member services”, who have an assortment of responsibilities that all relate back to two overarching objectives—keep the Members of Congress happy and help them succeed in achieving their goals. Additionally, leaders typically have “Floor assistants” to aide the party during debates in the House or Senate. Leaders will also often keep at least one legal counsel on staff, which a rank-and-file Member may not deem necessary, especially given limit in the number of assistants they may hire. The Speaker also has authority over the House’s Chamber, rooms and grounds, so he will hire a staff member to assist him in carrying out these duties.

Although leadership staffers have varied roles, they all have certain considerations and pressures that typical personal office staff do not. For example, party leaders have two constituencies: the voters back in the state or district and their colleagues in Congress. If a leader dissatisfies voters, he’ll quickly be out of a job. (House Speaker Thomas Foley was defeated for reelection in 1994 and House Majority Leader Eric Cantor lost a primary election in 2014 in part because they lost the confidence of key constituencies back home.) But if his colleagues in Congress are sufficiently displeased, he might be forced to resign his leadership post or lose it while running for reelection. (Although a Member who resigns from leadership does not have to resign his seat, he typically does so, since why go back to being a backbencher?) In addition to keeping an eye on local sentiment, leadership staff must also be sensitive to national public opinion. Some Members of Congress push leaders to adopt positions that are popular with their own supporters but which would be politically and legislatively suicidal if the party as a whole adopted them; other equally strong or stronger factions often oppose movements for unpopular positions. Leadership staff, then, must help their boss’ balance what various factions of the party want to do against what it should do to achieve their overall goals and what it must do to stay in or achieve the majority. These are only a couple of the concerns leadership staff have that most of their colleagues in other offices don’t. It takes an enormous amount of political skill to address them all effectively.

And leadership staff typically do have considerable political skill. They are some of the most intelligent, hard-working and adept staffers serving Congress. Life as a congressional staffer is not easy. It’s hard to land a gig on the Hill, and once there, the responsibilities are heavy. Long hours take away from time with family, friends and other activities people in the private sector often enjoy. And the pay is relatively low for one of the country’s most expensive areas. A staffer for the average rank-and-file Member won’t last long without dedication and skill—but the staffers for congressional leaders must excel even those high expectations.

Leadership staff need to be highly skilled since there is virtually no part of the legislative process that they do not touch. All sorts of bills, especially the most significant legislation with the potential to stir up the passions and significantly shape the country’s future, come about because of the policies leadership staff develop and the negotiations they conduct. They draft the messages that leaders deliver to their colleagues, the media, lobbyists, and most importantly, the general public. If there’s an ethics scandal, staff advise the leader on how to respond. If a foreign dignitary comes to Congress, they ensure that the proper protocols are observed—even to the point of advising what neckwear is best when the Pope comes to visit. The modern Congress would not function without leadership staff.

Many in Washington, including former chiefs of staff to congressional leaders, are already praising Ryan’s choice for chief of staff. Hoppe served as chief of staff to former Senate Majority Leader Trent Lott, so he understands the Senate deeply, and strong House-Senate relations will be key for a productive Republican majority. Other staff positions are still being decided—but it’s certain they will be every bit as capable and dedicated as the hundreds of leadership staffers who have preceded them over the years.

To learn more about leadership staff and congressional staff in general, check out Surviving Inside Congress, the Congressional Institute’s guide to Capitol Hill.