Abstract
Modern interest groups frequently utilize email communications with members as an organizational and informational tool. Furthermore, the nature of email communications—frequent, abundant, and simple to collect—makes them an excellent source of data for studies of interest groups. Nevertheless, despite the substantive importance and methodological possibilities of email communications, few interest group scholars have taken advantage of this data source due to the lack of a comprehensive, systematic database of email texts. This article makes the case for emails as a form of (big) data in the interest group field and discusses best practices for compiling and analyzing datasets of interest group emails. The article also introduces the Political Group Communication Database—the first large scale database of interest group and think tank email communications—and discusses the utility of this (and related) data for answering perennial and newly emergent questions in the interest group field.