The letter-book of William of Hoo is a hybrid between a formulary and letter-book with over 200 entries. It begins with fifty six entries which are pure forms, with initials instead of names or places and no dates, and ends with more or less complete copies of letters with full names and dates. William of Hoo was the sacrist of Bury St Edmunds from 1280-1294. As such he owned many manors and was virtually lord of the borough of Bury St Edmunds, he not only drew the rents, tolls and other profits of the borough but also presided over the borough court, held the view of frankpledge, was in charge of the song school and grammar school, and of the mint, and was responsible for enforcing of the assizes of weights and measures, and bread and ale. As the Abbot's deputy he also performed the functions of archdeacon. The letter-book illustrates his varied activities with entries concerning the probate of wills, matrimony and the enforcement of morality in the borough.