Arnold R. Weber had a long history in academia prior to his election at Northwestern. His teaching career began at M.I.T., where he was an Assistant Professor of Industrial Relations from 1957-58. He was recruited by a former professor and mentor to the faculty of the Graduate School of Business at the University of Chicago, where he taught from 1958 until 1973, as the Isidore Brown and Gladys Brown Professor of Urban and Labor Economics from 1971-1973. In 1973 he moved to Carnegie Mellon University where he served as Dean of the Graduate School of Industrial Administration from 1973-1977. He then held the post of Provost and taught as a professor of economics and public policy until 1980. Between 1980 and 1984, when he left to accept the presidency of Northwestern, Weber oversaw the University of Colorado as its President. During his time there, he cut deficits while increasing standards for admissions and academics.

Beyond his work at universities, Weber was extensively involved in government and public administration. From 1970 to 1971 he was the Associate Director of the Office of Management and Budget. In 1971, during the wage and price freeze, he spent 90 days as Executive Director of the Cost of Living Council. He was an economic consultant to the Secretary of the Treasury from 1976 to 1979 and a member of the Economic Advisory Committee to the U.S. Secretary of Commerce from 1980 to 1982. August, 1982, also saw Weber as Chairman of the Presidential Railroad Emergency Board seeking to head off a possible train strike.

Following his retirement from the Northwestern Presidency, the next several years saw Weber remaining active on both a local and national scale. Immediately upon leaving office, his name arose in consideration for Major League Baseball Commissioner, though he officially withdrew quickly. He followed his predecessor's footsteps becoming University Chancellor in 1995, and on June 30, 1998 was named President Emeritus, the first since Franklyn B. Snyder. During this time he also served as President of the Civil Committee of the Commercial Club of Chicago, an organization of the leaders of major Chicago corporations.