“Back to the Root” constitutes the proceedings of the 15th Fachtagung of the Indogermanische Gesellschaft, held in Vienna 13-16 September 2016.Despite the prominence of the general concept of the root in the reconstruction of the Indo-European proto-language (and in linguistic theory), the properties of Indo-European roots have so far received comparatively little in the way of detailed investigation. The 23 peer-reviewed papers by 27 scholars in this volume present a first step in this direction, and they constitute a quite diverse, but nevertheless always motto-related collection of papers.One paper takes a critical look at the concept of the root itself (Götz Keydana), another focuses on a formal constraint on the PIE root (Ignasi-Xavier Adiego), and two discuss certain structural subclasses of PIE roots (H. Craig Melchert, Thomas Steer).Four papers mainly deal with formally marked classes of roots in single branches (Bettina Bock/Sabine Ziegler, Ronald Kim, Georges-Jean Pinault, Oliver Plötz). Two contributions have a special focus on roots and verbal morphology (Davide Bertocci, Miguel Villanueva Svensson).Three papers deal with various aspects of adjectival roots (Stefan Höfler, Rosemarie Lühr, Alan J. Nussbaum); five contributions take a closer look at specific roots (Máté Ittzés, Jay H. Jasanoff, Elisabeth Rieken/Ilya Yakubovich, Nicholas Zair, Marina Zorman), and two further papers are about suppletive root patterns (Kristina Becker/Theresa Roth, José Luis García Ramón). Finally, the papers by Norbert Oettinger and Guglielmo Inglese/Silvia Luraghiweiterlesen