The first movement of the Piano Quintet, Op. 16 of Ludwig van Beethoven works out three significant motivic "topics": a chromatically filled-in second, appearing first as 5 - #5 - 6 (Bb - B - C in Eb major); the emphasis om the submediant, both as vi in Eb major and as the tonal region of C minor; and the melodic interval of the sixth, which, when inverted to become a descending third, determines the structure of tonal regions at crucial points in the movement. These three motivic topics are introduced in the opening measures of the piece and are subsequently unfolded throughout the movement; the focus of the thesis will be to trace the unfolding of these three topics.