Haydn's approach to form is underserved by current theories as discussed by Burstein (2016), Duncan (2011), Fillion (2012), Korstvedt (2013), Ludwig (2012), Neuwirth (2011, 2013), and Riley (2015). Comparing Haydn to composers a generation younger (Mozart and Beethoven) instead of with his contemporaries (such as Dittersdorf and Vanhal) distorts what is, and what is not, idiosyncratic about his compositional form. His inclination to reuse the opening theme later in the movement can impact the melody of his S theme, the path to and through his recapitulations, and the construction of his phrase's middles (Miyake, 2011). This compositional feature, however, often leads to forms that do not fit neatly into theories of Classical Era form forwarded by Caplin (2001) and Hepokoski and Darcy (2006). The concept of thematic saturation provides a window into investigating how Haydn reuses themes. The quantity and density of thematic saturation measure different aspects of thematic reuse and further our understanding of Haydn's approach to form. This project is part of a larger project that investigates whether patterns of thematic returns are independent of traditional formal designations (sonata form, sonata rondo, ABACA).