The new music theatre of the third quarter of the twentieth century presents a research field of great richness. In these years, music theatre became one of the main preoccupations for (especially) young composers digesting the consequences of the revolutionary experiments in musical language that followed the end of the Second World War. Despite the importance of 'music theatre' in this period, many significant works are now almost forgotten, and very few regularly revived, often because of the inadequacies of surviving notations or the unusual demands of staging.