In 1993 Rempis began a degree in classical saxophone at Northwestern University but quickly ditched the music degree to pursue studies in anthropology and ethnomusicology. As part of these studies, he spent a year at the Internation Centre for African Music and Dance at the University of Ghana, Legon, studying African music and ethnomusicology. He also continued to perform with many different types of groups, ranging from highlife and reggae bands while in Ghana, to jazz, free jazz, funk, and contemporary music ensembles at home.

Upon graduating, Rempis decided to focus on performing, and in March of 1998 was asked to replace saxophonist Mars Williams in the well-known Chicago jazz outfit The Vandermark Five. This opportunity catapulted him to notoriety as he began to tour regularly throughout the US and Europe playing clubs, concert halls, and festivals on both continents. Rempis also began to develop the many Chicago-based groups for which he is currently known. These include The Rempis Percussion Quartet, The Engines, The Rempis/Rosaly Duo, The Outskirts, Ballister, The Rempis/Daisy Duo, Bishop/Rempis/Kessler/Zerang, and Wheelhouse.