Using iPods or portable CD players, millions of people take their music with them every day to modify their daily experiences. Encased in headphones, they listen to music for entertainment, but also use it, among other things, as a buffer between themselves and the world outside, and to manage their moods. What is it about music that makes it useful in different ways to so many people? Have people always used music in these ways, or only since the technology of the Walkman and then the mp3 player made music portable? In this wide-ranging exploration of how and why we use portable music, Andrew Williams sheds new light on the role music plays in our everyday lives. Portable Music and Its Functions will be of use to students and scholars of sociology and cultural studies as well as of musicology.