"Overall, De Concilio has done legal historians a service by editing and translating this complex text in a clear and accessible manner and providing a lucid and concise discussion of its importance (though one should have copies of Gratian's Decretum and the Corpus Iuris Civilis at hand to make the most of it). The book offers a fascinating look into the twelfth-century legal classroom, especially the sorts of questions and problems that occupied canonists in this period and the methods they used to address them. It will be most useful to legal historians interested in the development of legal ideas and the ius commune at this critical moment in legal history, but those interested in scholasticism, the development of the universities, and, more generally, how ideas spread in the intellectual fervent of the twelfth century (especially outside the great schools of Paris and Bologna) will also find much to occupy them."Patrick R. Morgan, California Institute of Technology, in The Medieval Review, 8 October 2025