Study of musical manuscripts from the fifteenth and sixteenth centuries, opening a window on piety, liturgy and musical life in late medieval society.The musical culture of the Low Countries in the early modern period was a flourishing one, apparent beyond the big cathedrals and monasteries, and reaching down to smaller parish churches. Unfortunately, very few manuscripts containing the music have survived from the period, and what we know rests to a huge extent on six music books preserved from St Peter's Church, Leiden. This book describes the manuscripts, their provenance, history and repertory, and the zeven-getijdencollege, the ecclesiastical organisations which ordered the music books, in detail. These organisations have their roots in fifteenth-century piety, founded on the initiative of individuals and townadministrators throughout Holland, principally to ensure that prayers and Masses were said for those in the afterlife. Music, both chant and polyphony, played an important part in these commemorative practices; the volume also looks at the choristers and choirmasters, and how such services were organised. ERIC JAS is a lecturer in music at the university of Utrecht.