Musician, multi-instrumentalist, producer and composer, active in a wide spectrum of genres from early to popular to contemporary classical music. Since 2002 he has been a member of Canor Anticus early music ensemble (est. 1970), in which he plays the alto and bass viols. With this ensemble he received the 2006 Adam Jarzębski Prize, awarded at the 16th Early Music Festival in Warsaw. He has given performances in Poland, Great Britain, Austria, Belgium, Czechia, Spain, the Netherlands, Germany, Switzerland, Turkey, Cyprus, Iceland, Latvia, Slovakia, Hungary, and elsewhere, performing with ensembles such as Il Giardino Armonico, Ars Nova, Orchestra of the Golden Age, Narol Baroque, Il Tempo, Capella Cracoviensis, Sabionetta, Polish Radio Symphony Orchestra (POR), Orchestra of the Grand Theatre – Polish National Opera, Warsaw and Szczecin Philharmonics, Sinfonia Varsovia, and the Polish Sinfonia Iuventus Orchestra. He was also a soloist in the Olsztyn Philharmonic Orchestra and at the Polish National Opera. He has shared the stage with such outstanding soloists and conductors as Giovanni Antonini, Krzysztof Penderecki, Łukasz Borowicz, Antoni Wit, Jacek Kasprzyk, Anna Mikołajczyk, Krzysztof Szmyt, James Oxley, Dirk Snellings, Kay Wessel, Władysław Kłosiewicz, and Jerzy Połomski. 

Apart from performing early music, Zalewski has also been a bassist, guitarist, and singer in popular music bands such as Rita Pax, Alters, and Kasai. Singer Mela Koteluk’s album Migawka with his participation became a gold record. Zalewski has appeared on more than twenty CDs, including seven Fryderyk-nominated albums and one Fryderyk winner.