The material presented below grew out of a study of episcopal administration in the diocese of Barcelona in the mid-fourteenth century. Among the bishops' registers which were analysed for the study, three proved especially important: two from the communia, or general, series, Notule communium 15 and 16 (NC 15 and NC 16); and one from the collations series, Registrum collationum 9 (CO 9), covering the years 1345–51. The registers record both a period – 1345–8 – of presumably normal diocesan administration, and the plague period – the so-called Black Death struck Barcelona in spring 1348. The communia and collations series were selected both because they provided information about general diocesan administration and because the two series were conflated beginning with NC 15 in 1348, and remained separate until 1361.