In 1991, Obama accepted a two-year position as Visiting Law and Government Fellow at the University of Chicago Law School to work on his first book.[45][46] He then taught constitutional law at the University of Chicago Law School for twelve years, first as a Lecturer from 1992 to 1996, and then as a Senior Lecturer from 1996 to 2004.[47]

From April to October 1992, Obama directed Illinois's Project Vote, a voter registration campaign with ten staffers and seven hundred volunteer registrars; it achieved its goal of registering 150,000 of 400,000 unregistered African Americans in the state, leading Crain's Chicago Business to name Obama to its 1993 list of "40 under Forty" powers to be.[48]

He joined Davis, Miner, Barnhill & Galland, a 13-attorney law firm specializing in civil rights litigation and neighborhood economic development, where he was an associate for three years from 1993 to 1996, then of counsel from 1996 to 2004. His law license became inactive in 2007.[49][50]

From 1994 to 2002, Obama served on the boards of directors of the Woods Fund of Chicago, which in 1985 had been the first foundation to fund the Developing Communities Project, and of the Joyce Foundation.[31] He served on the board of directors of the Chicago Annenberg Challenge from 1995 to 2002, as founding president and chairman of the board of directors from 1995 to 1999.[31]