Readers of this journal will surely have noticed the remarkable proliferation in the past few decades of “handbooks” and “companions” devoted to major – and even obscure – topics, thinkers, and actors in religious history. The simultaneous appearance in 2021 of The Oxford Handbook of Calvin and Calvinism and Brill's Companion to the Reformation in Geneva provides an opportunity to reflect on the character and value of such volumes, the conditions of their production, and the reasons for their recent proliferation. Also discussed here for purposes of comparison will be an ambitious collection of essays of a more conventional sort: Protestant Empires: Globalizing the Reformations , edited by Ulinka Rublack. ¹