Complex sentence: As of 1976, he served as distinguished professor of sociology at Binghamton University until his retirement in 1999, and as head of the Fernand Braudel Center for the Study of Economies, Historical Systems and Civilization at Binghamton University until 2005.
Split into simpler sentences: As of 1976, he served as distinguished professor of sociology at Binghamton University until his retirement in 1999. Wallerstein was head of the Fernand Braudel Center for the Study of Economies, Historical Systems and Civilization at Binghamton University until 2005.