Sweet has served in a variety of professional leadership positions. At UW-Madison, he directed the African Studies Program (2012-2013), chaired the Department of History (2013-2016), and chaired the Department of Spanish and Portuguese (2017-2020). He was an elected Councilor of the Research Division of the American Historical Association (2016-2019). He sat on the editorial boards of Luso-Brazilian Review, The Americas and Journal of Africana Religions. He is also a book series editor for the University of Wisconsin Press.