jats:titleAbstract</jats:title> jats:pThe Willmott and Braikenridge manuscripts, once owned by the Norwich merchant John Sadler (d.1592), are all that is known to survive from his second partbook set, dated 1591. This article explores the custodial history of those volumes, tracing their various later owners and the marks they left. It finds that the two surviving volumes may have been apart since 1709—a separation that persisted until they were reunited in 2022—and also that the set’s three missing partbooks may have been lost only since 1885, raising hopes that they may one day be found.</jats:p>