A Term Catalogue (German: Messkatalog) is a serial publication compiled to inform customers—most importantly book traders from other cities—of the book production as available on the book fairs. The first such catalogue was issued by Georg Willer in Augsburg in 1564. Several projects followed the model including the series of English Term Catalogues issued by John Starkey and Robert Clavell under the title Mercurius Librarius, or, a catalogue of books from 1668 to 1711. "Term" referred to the dates of the fairs that would be held as platforms of the trade. The catalogues are a valuable source to researchers today, because they often give dates of the publication processes and information about working titles that were eventually dropped. The segmentation is of interest for its contemporary perspective on the market: a perspective modern literary histories no longer share. German Messkataloge, 1564 to 1860 The book trade of the German-speaking territories was for more than a century the model of all further European developments. The technological achievement of the printing press spread in Germany without the focus on a capital. Germany had cultural centre but a network of cities and territories in different affiliations. A fragmented decentralised geographical space had to be provided with books. Relatively small towns of 20,000 to 40,000 inhabitants created as early as the 1470s and 1480s the basic network of the new trade. Central fairs in Nördlingen, Frankfurt and Leipzig offered publishers from all over Germany, Austria and Switzerland in the course of the 16th century the option to change books they had published and thus to widen the scope of titles they could sell in their respective shops at home. The first Term Catalogue published by Georg Willer in Augsburg in 1564 was supposed to inform his customers in Augsburg about books he had brought home from the last Frankfurt fair. Within the next two years his catalogue became an interesting platform Frankfurt traders would use to observe the market. Willer arranged to have his catalogue printed in Frankfurt where it soon turned from a retrospective into a prospective medium, into a catalogue issued to list all the books that would be offered on the upcoming fair. His first catalogue showed a strong Latin production. Almost 73% percent of the titles he listed were published in the language of erudition. Most of the books fell into the theology sections. The four university faculties theology, law,