These compositions have been created with a view to explore a soundworld inspired by different genres within the realm of music in theatre, primarily opera and musical theatre. The music I have written reflects the research that I have conducted of these genres, and demonstrates musical elements that are frequently associated with each genre, but not typically used together in one piece of music. I have chosen to focus primarily on these two genres because I am intrigued by the vastly different critical reception, public perception and general popularity of the art forms. The chasm in the reception of these two examples of music in theatre is made all the more interesting given the fact that they are (seemingly) very similar genres. The following dissertation details the research that I have completed prior to completing the compositions more explicitly, and serves to further validate the portfolio of music as a product of academic investigation.