In this sparkling and carefully researched book, Phil Kilroy presents fresh insights into the Society of the Sacred Heart, a community of women religious founded in France in 1800. Kilroy has previously published a most successful biography of the Society's founder and leader, Madeleine Sophie Barat (Cork 2000). Comments and questions from the international readership of that biography, including academics and members of the Society of the Sacred Heart, convinced Kilroy that various issues required further investigation. When a researcher embarks on a new study that is closely related to previous work there are inevitable risks of repetition and staleness. But Kilroy has done well to avoid such traps. In the introduction she establishes the different aims of this book, identifying the five topics which she goes on to explore in the chapters: the evolution of the Society, its educational model, interaction with the Jesuits, medical biography, and Barat's spiritual leadership. Each chapter is intended as a distinct essay, so this is not the kind of book to advance a core argument building up the analysis as it goes along. There is no need for the reader to have read the biography of Barat first because discussion of her life is integral to the account that Kilroy gives of the community. Like so many associations begun by a few committed individuals, the Society of the Sacred Heart evolved in a haphazard way and faced numerous practical challenges to growth. Its first members were a cluster of women who in 1800 lived in Paris's rue de Touraine (now rue Saintonge). These women gradually forged links with other women in Amiens, Grenoble and Poitiers during the first decade of the nineteenth century. Members of the Society were committed to establishing small boarding schools and poor schools to provide Christian education to pupils of any social background in post-revolutionary France. Barat's leadership was frequently contested by certain women within the Society and also by male priests who wanted to wrest control from her. Barat's great abilities as leader enabled the Society to preserve its unity of purpose, even as the community grappled with internal differences of opinion on practical and spiritual matters. Kilroy explains these membership politics in engaging detail, revealing the thoroughness of her archival research and empathy for her historical subjects. Especially memorable is the chapter on medical biography where Kilroy draws on Barat's letters – of which some 14,000 survive – to document the physical ailments of the Society's founder and their implications. With reluctance, Barat was forced to adjust certain aspects of her leadership (for example, in the area of religious fasting) according to what her body was able to support without falling ill. Kilroy's excellent essay on medical biography will be of special interest to the growing numbers of historians interested in the ways in which people in the past wrote about health and emotions. It is just one of the reasons why this original and fascinating book seems certain to attract a wide readership.