The International Tectonic Lexicon comprises a first selection of important tectonic terms, explains their meaning and suggests equivalents in the six languages of the International Geological Congress: English, French, German, Italian, Russian, and Spanish. The format of this volume follows that of its predecessor, to which the reader is referred for a brief history of the International Tectonic Lexicon project. We have now annotated more tectonic terms which, by consensus, seemed most relevant in geological documentation. We again solicit suggestions for inclusion in a third volume that is in the planning stage, and that will be completed if funding can be found. One of the satisfactions of this work has been the continuing international collaboration, both by correspondence and at the rare editorial conferences. It is hoped that the result will help others increase their international contacts.