From 1992 until his election to the U.S. Senate in 2004, Barack Obama served as a professor in the Law School at the University of Chicago Law School in Chicago, Illinois. He was a Lecturer from 1992 to 1996. He was a Senior Lecturer from 1996 to 2004, during which time he taught three courses per year.

Senior Lecturers are considered to be members of the Law School faculty and are regarded as professors, although not full time or tenure track. The title of Senior Lecturer is distinct from the title of Lecturer, which signifies adjunct status. Like Obama, each of the Law School's Senior Lecturers had high demand careers in politics or public service, which prevented full time teaching. Several times during his 12 years as a professor in the Law School, Obama was invited to join the faculty in a full time tenure track position, but he declined.

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