The Internal Revenue Service (IRS) is the revenue service of the United States federal government. The agency is a bureau of the Department of the Treasury, and is under the immediate direction of the Commissioner of Internal Revenue. The IRS is responsible for collecting taxes and the interpretation and enforcement of the Internal Revenue Code.

The IRS has its headquarters in Washington, D.C., and does most of its computer programming in Maryland. It currently operates five service centers around the country (in Austin, TX; Cincinnati, OH; Fresno, CA; Kansas City, MO; and Ogden, UT), at which returns sent by mail are received. These centers do the actual tax processing; different types of returns are processed at the various centers (with some centers processing individual returns and others processing business returns). The IRS also operates three computer centers around the country (in Detroit, Michigan; Martinsburg, West Virginia; and Memphis, Tennessee).

In July 1863, during the Civil War, President Abraham Lincoln and Congress created the office of Commissioner of Internal Revenue and enacted a temporary income tax to pay war expenses (see Revenue Act of 1862). The position of Commissioner exists today as the head of the Internal Revenue Service.

John Koskinen served as Non-Executive Chairman of Freddie Mac from September, 2008 to December, 2011, retiring from the Board in February 2012. He served as President of the U.S. Soccer Foundation from 2004-2008. He previously served as the Deputy Mayor of the District of Columbia, the Deputy Director for Management of the Office of Management and Budget, and Chair of the President's Council on Year 2000 Conversion, the Year 2000 problem. He presently also serves on the boards of AES and American Capital, Ltd. On March 11 2009 he was announced as the interim CEO at Freddie Mac. On April 23 2009 he became the Principal Financial Officer after the death of Freddie Mac's acting CFO. In August, 2009, with the hiring of a new CEO, he returned to his position as non-Executive Chairman of the Board of Freddie Mac.

Prior to entering government service, he worked for 21 years for the Palmieri Company as Vice President, President, CEO and Chairman. Koskinen also chaired the Washington, DC Host Committee for the 1994 World Cup and the Duke University Board of Trustees. He is a graduate of Duke University, Yale Law School and attended Cambridge University.

Harold Watson "Trey" Gowdy III (born August 22, 1964) is the U.S. Representative for South Carolina's 4th congressional district. He is a member of the Republican Party. Before his election to Congress, he was the solicitor (district attorney) for the state's Seventh Judicial Circuit, comprising Spartanburg and Cherokee counties.

He was born in 1964 in Greenville, South Carolina, the son of Novalene (née Evans) and Dr. Harold Watson "Hal" Gowdy, Jr. Trey graduated from Spartanburg High School in 1982. He earned a B.A. in history from Baylor University in 1986 and a law degree from the University of South Carolina School of Law in 1989.

Following law school, he clerked for the late John P. Gardner on the South Carolina Court of Appeals and United States District Court Judge Ross Anderson. He then went into private practice before becoming a federal prosecutor in April 1994. He was awarded the Postal Inspector’s Award for the successful prosecution of J. Mark Allen, one of “America’s Most Wanted” suspects.

Paul Davis Ryan (born January 29, 1970) is the U.S. Representative for Wisconsin's 1st congressional district, serving since 1999. He is a member of the Republican Party, and has been ranked among the party's most influential voices on economic policy.

Born and raised in Janesville, Wisconsin, Ryan graduated from Miami University in Ohio and later worked as a marketing consultant for Ryan Incorporated Central, run by a branch of his family. In the mid to late 1990s, he worked as an aide to United States Senator Bob Kasten, as legislative director for Senator Sam Brownback of Kansas, and as a speechwriter for former U.S. Representative and 1996 Republican vice presidential nominee Jack Kemp of New York. In 1998, Ryan won election to the United States House of Representatives, succeeding the two-term incumbent, fellow Republican Mark Neumann.

Ryan currently chairs the House Budget Committee, where he has played a prominent public role in drafting and promoting the Republican Party's long-term budget proposal. He introduced a plan, The Path to Prosperity, in April 2011 as an alternative to the budget proposal of President Barack Obama, and helped introduce The Path to Prosperity: A Blueprint for American Renewal in March 2012, in response to Obama's 2013 budget. Ryan is one of the three co-founders of the Young Guns Program, an electoral recruitment and campaign effort by House Republicans. He endorsed Republican presidential candidate and former Governor of Massachusetts Mitt Romney for the 2012 United States presidential election. Ryan has been considered as a possible running mate for Romney.

Darrell Edward Issa (/ˈaɪsə/; Arabic: عيسى‎; born November 1, 1953) is the U.S. Representative for California's 49th congressional district, serving since 2001. He is a member of the Republican Party. He was formerly a CEO of Directed Electronics, the Vista, California-based manufacturer of automobile security and convenience products. His district consists of portions of southern Riverside County and northern San Diego County. The district was numbered as the 48th District during his first term and was renumbered the 49th after the 2000 Census. Since January 2011, he has served as Chairman of the House Oversight and Government Reform Committee.

Issa is a self-made millionaire with a net worth estimated between $220 and $448 million, making him one of the wealthiest members of Congress. He was a major contributor to the 2003 recall election of Governor Gray Davis.

Issa was born in Cleveland, Ohio, the second of six children. His mother was a Mormon and his father Eastern Orthodox. Issa is the grandson of Lebanese immigrants.