The subject of aesthetic experience as it relates to music embodies a vast and fascinating territory of philosophical thought. Ancient philosophers to modern musicologists have engaged in scholarly debate over the topic from many perspectives (Davies, 2010; Kivy, 1989). Not surprisingly, a similar intrigue surrounds questions regarding the clinical value of aesthetic aspects of music and of music making for health, healing, and human development (Aigen, 1995, 2007).

Numerous links between aesthetic experience and therapeutic processes are found in the music therapy literature. In fact, volumes could be filled with theories and philosophical arguments for and against the meaning and/or meaningfulness of aesthetic experiences in healing, such as those found in music therapy treatment processes. However, in this chapter, I delimit our exploration to an assortment of perspectives that address, arguably, one of the most clinically relevant aspects of the aesthetic music experience: that of emotion and its expression in or through music (Eerola & Vuoskoski, 2013). More specifically, I focus on a client's active music-making processes wherein emotions might be ex- pressed in or through music rather than being elicited by music. I consider sources of emotion and where emotions might be located within music-making processes. And finally I explore theories that variously explain how musical expressions of emotions might occur. These theories provide guidance for the music therapist who wishes to understand and respond to the potential emotional meanings of a client's music making. In fact, to gain insights about a client's emotional world via music making is a unique and clinically powerful facet of music therapy.