Heitor Villa-Lobos (1887-1959) is known largely as a Brazilian nationalistic composer and as a pedagogue who played a huge role in establishing Brazil’s musical national identity. However, little has been written about his chamber works, particularly his seventeen string quartets. This DMA document seeks to begin to fill this gap in the literature by focusing on Villa-Lobos’s third quartet. Written in 1916, this quartet is a snapshot of a time when he was still developing his musical voice. Because the Brazilian elements of his music became significantly more prominent in the latter two-thirds of his life, many scholars dismiss the earlier works as derivative of his European contemporaries. This document will demonstrate the reverse, through a thematic study of one of Villa-Lobos’s early quartets, Quartet No. 3. Additionally, this paper will provide biographical information to contextualize the piece and discuss influences of Brazilian popular music on Villa-Lobos’s chamber music, particularly Quartet No.3. It will also lay out a thematic study of each of the movements by identifying the themes, their influences, as well as some contrapuntal observations, and will address some of the performance practice issues relating to Villa-Lobos’s use of texture, instrument roles, and string techniques.