This edition of archival sources, volume xvi in the excellent series Westfalia Sacra, makes available the protocol of the visitation to the southern parishes (the Oberstift) of the bishopric of Münster, carried out by the auxiliary-bishop, Arresdorf, and the vicar-general, Hartmann, between the years 1613 and 1616. A previous volume (vol. xiv in the series) on the northern part of the bishopric (the Niederstift) was published in 2004. There is now a number of excellent studies and documentary editions of diocesan visitations, primarily for Italy, France and the Holy Roman Empire. This particular visitation was especially important. It was not the first attempt at Tridentine reform in Münster. A previous visitation was carried out between 1571 and 1573 under Bishop Erich von Hoya, which turned up evidence of ubiquitous clerical concubinage and extensive communio sub utraque specie. Strong opposition to disturbing the status quo dissuaded Hoya from taking any action with regard to Catholic reform. But on the eve of the Thirty Years' War, Prince-Bishop Ferdinand, a Wittelsbach and a strong supporter of the Counter-Reformation, appointed the non-Westphalians Arresdorf and Hartmann to undertake a thorough investigation. The protocol is arranged by parish and reports the answers to a list of questions posed by the visiting churchmen. In addition to information on the state of ecclesiastical buildings, church finances, the congregations, the administration of sacraments, the most interesting information concerns the status of the clergy. While there were clear signs of progress in the Tridentine sense since the Hoya visitation, it is remarkable how persistent a regional and local Catholic identity remained, as measured in clerical concubinage and deviation from the Roman rites. This excellent edition of the visitation protocols includes an extensive discussion of the historical background and of the manuscripts, as well as indices of personal and place names.