These are the proceedings of the Third Congress on Technological Innovation for Specialized Linguistic Domains (TISLID'18), which took place in 24-26 May 2018 at Ghent University, Belgium. This event was hosted by the UGent-based research groups MULTIPLES and LT3 in collaboration with the UNED-based ATLAS group. This volume captures a great deal of the knowledge and experiences that were shared there, related to the digital realities and methodological innovation involved in the use, processing and learning of languages and, specifically, those used in specialized domains. The first part deals with various issues related to language technologies; the second part focuses on work on technology-enhanced language learning; and the third part focuses in more depth on three modalities within TELL which are receiving particular attention from the research community nowadays: mobile, open and social language learning. This book will be useful for postgraduate students, practitioners and researchers interested in the common spaces between Information and Communication Technology and Languages for Specific Purposes in the context of our increasingly digital occupations, cultures and lives.