From 1979 to 1981, Salam was a lecturer on the contemporary history of the Middle East at Sorbonne University. In 1981, he left Paris to spend an academic year as a visiting scholar at the Weatherhead Center for International Affairs at Harvard University. Between 1985 and 1989, he was a lecturer at the American University of Beirut, during which time he also practiced law as an associate at Takla Law Firm. He was a visiting researcher at Harvard Law School from 1989 to 1990, and a foreign legal consultant at Edwards & Angell LLP from 1989 to 1992. He resumed his practice at the Takla Law Firm in 1992 as well as his teaching of International Law and International Relations at the American University of Beirut. He was appointed Visiting associate professor of Political Science in 2003, and later associate professor of Political Science in 2005. From 2005 to 2006, he was the Chairman of the Political Studies and Public Administration Department.
