Over the last two decades, the notion of institutional thickness has become a key reference for a large body of work that has sought to provide profound insights into the link between institutions and regional development. However, only few attempts have been made to reassess the concept, to improve its methodology, and to reflect on its empirical application. The aim of this article is to revise the original concept of institutional thickness. We draw on and seek to contribute to current work in economic geography and related disciplines on the role of organizations and institutions in regional development. We identify some crucial limitations and provide suggestions for how they can be addressed. It is argued that much can be gained by (1) explicitly elaborating on the relation between the organizational and institutional dimensions of thickness, (2) moving beyond overly static views on thickness, (3) developing a multiscalar approach to thickness, and (4) identifying features for assessing thickness in absolute and relative terms. © 2017 Clark University.