Improvisation and Inventio in the Performance of Medieval Music: A Practical Approach is an innovative and groundbreaking approach to medieval music as living repertoire. The book provides philosophical frameworks, primary-source analysis, and clear, actionable practices and exercises aimed at recovering the improvisatory and inventive aspects of medieval music for contemporary musicians. Aimed at both instrumentalists and vocalists, the book explores the utilization of musical models, the inventive implications of medieval notation, and the ways in which memory, mode, rhetoric, and primary source paradigms inform the improvisatory process in both monophonic and polyphonic music of the Middle Ages. Angela Mariani, an experienced performer of both medieval music and folk and traditional musics, rediscovers and explicates the processes of imagination, invention, and improvisation which historically energized both medieval music in its own period and in its revival in our own time. Based on decades of research, university teaching, ensemble direction, collaboration, and performance, Mariani's impassioned stance that 'the elusive element of inventio, as the medieval rhetoricians would have called it, must always be provided by the performer in the present,' emphasizes medieval music performance practice as a dynamic and still-vital tradition. Students, teachers, directors, and those interested in the wealth of expressive beauty found in the music of the middle ages will likewise find value and meaning in her clear and accessible prose, and in the practical processes and exercises that make this book unique within the literature of medieval performance practice.