Aaron Coplands Clarinet Concerto written in 1948 for the jazz clarinetist Benny Goodman is one of todays most important American pieces of the clarinet repertoire. During the composition process of the Clarinet Concerto Copland was traveling as a cultural ambassador in South America. The local music he experienced in Brazil inspired him to incorporate Brazilian folk music in the Clarinet Concerto. This research investigates the Brazilian influences in the Concerto based on Coplands musical experiences in the Brazilian state capitals of Rio de Janeiro, Sao Paulo, Recife, and Salvador. It provides a performance practice guide of Brazilian music through a discussion of the popular musical styles frevo, samba, and choro, as well as concert works by the Brazilian composers Heitor Villa-Lobos and Camargo Guarnieri.Guided by Brazilian music performance traditions, this document offers an alternative performance perspective of the Clarinet Concerto that embraces its Brazilian influences, and contributes to the Pan-American character of Coplands musical style.