This book falls within the series Medieval Law and Its Practice. However, it might be called The Diversity of Medieval Canon Law. The editors' introduction underlines the changes in the study of medieval canon law in recent decades. These changes emphasize the detailed study of individual legal texts, the use of philology in these studies and the grounding of law in regional practice, especially before the vulgate text of Gratian's Decretum became dominant in the university-level study of law. The collection concludes with a Postface by Bruce Brasington underlining the ways in which pre-Classical canon law was approached not as a system but as a set of options which could be chosen in the pursuit of results.

The studies in between underline these themes with well-documented examples. John S. Ott studies the papal judges delegate from the province of Reims in the early twelfth century. Those who were studied were bishops with histories of involvement in local cases, including as facilitators of agreements on controversial issues. Ott concludes, rightly, that the papacy assigned cases to respected prelates whose interventions in cases were likely to be well received. Mia Münster-Swendsen tackles the documentation of the resignation of Archbishop Eskil of Lund. Eskil was on the losing side of Danish politics. The response of Pope Alexander III to the archbishop's query about resignation is presented as deliberately ambiguous, stating the principle of non-resignation while allowing Eskil to gain release from a losing situation by giving up his episcopate.

The second pair of studies is more theoretical. Melodie Eichbauer compares the opinions on property issues, including tithes, of Gratian and Stephen of Tournai. Although Gratian once was regarded as a monk, the author reveals how the Decretum favors the rights of bishops in those matters. Stephen, a long-time Augustinian abbot before being elevated to the episcopate, favored the interests of monasteries. Jason Taliadoros tackles a very theoretical topic, the extent to which twelfth-century canonists can be cited in support of Brian Tierney's thesis that medieval writers opened the way for an idea of permissive natural rights. The author tests Tierney's thesis especially against the writings of the jurist Vacarius, underlining where his subject diverges from that line of thought. That approach raises the question whether all twelfth-century jurists have to agree with Tierney's line of argument as a step toward an ideology of personal rights.

The fifth and sixth studies focus on councils. Greta Austin deals with the 1023 Council of Seligenstadt. Although Burchard of Worms participated, his Decretum was not the sole source of the canons. The bishops drew on what the author calls a farrago of canons when formulating decrees. This shows how little a council felt obligated to use a well-known collection when legislating. Danica Summerlin does a similar study of the 1200 Council of Westminster. Archbishop Hubert Walter and his bishops were aware of the canons of Alexander III's Third Lateran Council (1179). Although Third Lateran is regarded as a general council, there is no evidence that the English bishops felt obligated to turn all of Alexander's conciliar decrees into a complete set of local enactments.

Stephan Dusil and William L. North both deal with emerging jurisprudence. Dusil shows the Second Lateran Council (1139) issuing a canon annulling the marriages entered into by higher clergy (subdeacons, deacons and priests). This canon abandoned an older acceptance of those marriages as legitimate. The canonists gradually develop this prohibition into an impediment to valid marriages. North presents an intriguing study of the thought of the reformer Bonizo of Sutri. Bonizo developed some of the dicta Gratian used in the Decretum. The texts he wrote sought to teach aspiring clergy how to interpret the many canons in circulation in the late eleventh century.

The remaining contributions differ from one another. Kathleen G. Cushing examines the use of canon law in the libelli de lite from the time of Gregory VII. Both the pope's supporters and his foes used these sources. Both appealed to the law as supporting them. In no case did their use of the canons presage the formal canonical jurisprudence which took shape in the new-born universities. Like Roger Reynolds, Louis I. Hamilton sees differences between canon law and other genres of writing as scarcely discernible in the eleventh and twelfth centuries. This study looks at the use of Scripture in theCollection in 74 Titles and the exegetical text by Bruno of Segni. Those works display that lack of strong methodological boundaries. Hamilton rightly sees the appeal to Scripture in the reforming context as creative, all the more so since it was not part of a tidy drive toward uniform ecclesial structures.

Overall, this useful collection extends our reach beyond tidy boundaries separating canon law and other genres. It shows too a creative interplay between shared texts and local practice. Instead of simply blazing the way for the vulgate version of the Decretum and its commentators, these prelates, clergy and lay authorities applied their wits to a complex heritage in a lively pursuit of remedies for the problems they faced day to day.​