Those whose thoughts of musical theatre are dominated by the Broadway musical will find this book a revelation. From the 1850s to the early 1930s, when urban theatres sought to mount glamorous musical entertainment, it was to operetta that they turned. It was a form of musical theatre that crossed national borders with ease and was adored by audiences around the world. This collection of essays by an array of international scholars examines the key figures in operetta in many different countries. It offers a critical and historical study of the widespread production of operetta and of the enthusiasm with which it was welcomed. Furthermore, it challenges nationalistic views of music and approaches operetta as a cosmopolitan genre. This Cambridge Companion contributes to a widening appreciation of the music of operetta and a deepening knowledge of the cultural importance of operetta around the world.