Stephen Sondheim is often praised as one of the most prolific and exceptional musical theater composers of the 20th Century. In 1981, Stephen Sondheim experienced the biggest failure of his career with his passion project, Merrily We Roll Along. A few years following, he emerged back on the scene with a new writing partner James Lapine to write Sunday in the Park with George. This was a pivotal shift in Sondheim’s career so comparing these two musicals could give lots of insight into Sondheim’s musical development. This project will investigate these two works as equals and reveal Sondheim’s musical and thematic elements within them. I am using musical analysis methodology to allow the music to speak for itself and reveal the connections between the two larger works. Stephen Sondheim is a very unique composer, so a musical analysis has to be performed through many different lenses. While Sondheim employs a lot of common practice techniques when composing, perhaps the most effective way to view his music is through the emotions behind it. Despite these two musicals being written in two different compositional styles, the way that Sondheim is able to convey emotion stays consistent. His use of pedal point, bimodality, effect chords, and voice leading all seem to attempt to convey the emotion of that specific moment. Learning how and why brilliant composers create their work is a key element in the creation of new and exciting art. This project will supply musicians, composers, and educators with a prime example of how an artist was able to express his art freely and effectively.