In this short and energetic book, Nancy Siraisi explores the published collections of medical letters and correspondence networks of various German and Italian physicians active in the second half of the sixteenth century – a set of texts that Siraisi suggests could be characterized as a ‘minor genre of Renaissance learned medical discourse’ (p. 3). As a product of medical humanism, these letters both reflected admiration for an ancient literary form and provided a versatile forum for communication that allowed physicians to gossip about colleagues, discuss personal family matters, share clinical experience, debate future directions of the medical profession and engage in natural-philosophical disputes. Situating physicians’ letters within the concept of the Republic of Letters, Siraisi illustrates how they provide a unique source not only for medical historians, but for intellectual and social historians as well.

The book's three chapters reflect the fact that most collections of Latin medical letters were printed in Italy or the German lands. Chapter 1 addresses the manifest geographical differences between several types of medical practitioner who corresponded between northern and southern Europe. These include, among many others, the Venetian physician Nicolò Massa, the Heidelberg professor and vociferous anti-Paracelsian Thomas Erastus, and Girolamo Mercuriale from the medical faculty at Padua. Chapter 2 stays within the northern European context, focusing on the correspondence of the Heidelberg physician Johann Lange, whose collections of epistolae medicinales provide fascinating insight into the everyday experience of a practising court physician. Chapter 3 draws widely from the correspondence network of the Italian Orazio Augenio, who spent most of his career as a town practitioner near Le Marche, and for whom letters served, somewhat unusually, as a principal means of public discourse through which he cultivated relationships with practitioners and medical faculty members across Italy.

That the letters can be considered as members of a single genre should not imply a high degree of standardization. Indeed, their stylistic variety reflects their authors’ widely differing social and professional circumstances, which afforded them vastly different medical experiences. We see how physicians appropriated the genre for their own purposes as a result of their different situations, such as the way Augenio frequently used letters as a means of recruiting others to support him in his disagreements with medical colleagues. Siraisi points out, too, how Augenio's tendency to shotgun short treatises on medical topics into his letters stands in stark contrast to Lange's humanistic and stylistically self-conscious dialogues. Correspondents sometimes explicitly argued about preferred formulary conventions. Girolamo Mercuriale, for instance, drew a sharp contrast between his medical consilia, which he thought should convey only practical advice for individual cases and treatments, and other letters in which he endeavoured to advance his intellectual interests and agenda, such as his fifteen-year correspondence with Theodor Zwinger.

Siraisi highlights how physicians used the variegated letters as a forum for intellectual debate on virtually every medical topic. Against the backdrop of recurring outbreaks of disease, for example, many heated exchanges concerned the nature of putrefaction, contagion and the use of strong drugs (or poisons, according to some). Other discussions reflected on the medical profession as a whole, such as the role of innovation or the appropriateness of physicians compounding their own medicines. Siraisi carefully examines debates of these kinds within the broader cultural and intellectual frameworks of the authors, such as Lange's hostility to Jewish physicians and Augenio's long dispute with Alessandro Massaria over interpretations of Galen.

Even as sixteenth-century medical texts typically reflect the personality of the author, the letters (at least in Siraisi's capable hands) imbue these practitioners and professors with a historical vibrancy that many of their formal publications fail to capture. One does not need to look far to find striking examples of competition, professional jockeying, and personal attacks juxtaposed with apologies, collaboration, and mentoring. Siraisi repeatedly highlights the complexity and power of the correspondence networks, as when Arcangelo Mercenario wrote, seemingly innocuously, to Augenio about ‘some philosophical and medical problems’ that Augenio later found out were ‘a test of [his] intellectual powers’ (pp. 77–78). Mercenario subsequently published a denunciation of Augenio's reply; Augenio responded with another letter not only to enlarge and clarify his arguments, but also to note several personal issues that interfered with his letter writing and ought to mitigate his earlier reply.

As Siraisi mercilessly whets the reader's appetite, one may easily wish for more. With a larger canvas, for instance, Siraisi might have been able to foreground more of the letters themselves. Although she includes numerous excerpts, paraphrases, and a few extended quotations, one easily wishes for more of Siraisi's adept translations that bring such vivacity to the authors and their letters. Fortunately, exhaustive endnotes – they comprise a little less than half the book – provide ample Latin from the letters as well as additional primary and secondary sources for further consultation.

Needless to say, Communities reflects Siraisi's routinely thorough research and engaging prose, and it would be difficult to argue that the book does not accomplish what it sets out to do. She aptly demonstrates the importance of letter writing to physicians, illustrates how physicians used letters in different ways, and surveys the multitude of topics that physicians were eager to discuss with their letter-writing colleagues. Even as she explores particular conversational threads about medical theory and practice, she continually explicates the nature of the communication networks and how groups of physicians effectively forged geographically dispersed medical communities. As Siraisi readily admits, the letters give us far more than can be conveyed in a brief survey. Nonetheless, her synthetic and insightful analysis easily motivates additional study of both the letters and networks by showing how much these letters provide a new and vibrant perspective on early modern medical communities.