Madison Dearborn Partners (MDP) is a private equity firm specializing in leveraged buyouts of privately held or publicly traded companies, or divisions of larger companies; recapitalizations of family-owned or closely held companies; balance sheet restructurings; acquisition financings; and growth capital investments in mature companies.

Madison Dearborn Partners was founded in 1992 and is based in Chicago, Illinois. The founders of Madison Dearborn had previously made private equity investments for First Chicago Bank.

Madison Dearborn's chairman, John Canning, Jr., is also a minority owner of the Milwaukee Brewers baseball team and submitted an ultimately unsuccessful bid to buy the Chicago Cubs

In 1998, the firm bought Reiman Publications, based in Greendale, Wisconsin, from Roy Reiman for $640 million. In 2002, the firm sold Reiman Publications to Reader's Digest Association.

In 2007, the firm joined forces with Michael Eisner's Tornante investment company to buy out baseball card maker The Topps Company.

John A. Canning, Jr. is a private equity investor and sports executive. He is the founder and chairman of Madison Dearborn Partners, the large Chicago-based private equity firm. He has recently been linked to discussions about the potential sale of the Chicago Cubs.

Canning was an early investor in private equity in the late 1970s and early 1980s. Canning founded Madison Dearborn Partners in 1992. Since then the firm has raised over $14 billion of investor commitments. Prior to founding Madison Dearborn, Canning and his team had previously made private equity investments for First Chicago Bank. Canning joined First Chicago in 1968 and spent 24 years with the bank serving as Executive Vice President of The First National Bank of Chicago and later as President of First Chicago Venture Capital, the predecessor of Madison Dearborn.

Canning currently serves on the Boards of Directors of

Canning currently serves on the Boards of Trustees of:

Canning also serves as a commissioner of the Irish Pension Reserve Fund, a trustee and chairman of The Chicago Community Trust as well as a director and chairman of the Federal Reserve Bank of Chicago.

Jim O'Connor is an American actor and former host of the show The Secret Life Of.... O'Connor first appeared on the Food Network as the host of All-American Festivals, replacing Tyler Florence as host. Later O'Connor went on to host the new Food Network show, The Secret Life Of... for three years, until George Duran replaced him as host in early 2007. O'Connor also has hosted a special called Scoop, in which five Food Network viewers create a new flavor of ice cream.

O'Connor appeared in the movie Sweet Home Alabama as a reporter who holds a microphone out as Reese Witherspoon and Patrick Dempsey walk past the crowd after the engagement scene. He also appeared in the comedy movie Undercover Brother as a cigarette executive, and Mystic Pizza.

O'Connor also plays crime reporter Dean Reid on the Onion News Network. As Reid, O'Connor hosts Raw Justice, a parody newsmagazine in the vein of Dateline.