As central aspects of legal translation practice and research, legal terminology and phraseology are a prominent area of inquiry in Legal Translation Studies (LTS). This introductory paper reviews the varying conditions and challenges of dealing with conceptual incongruity in inter-systemic legal translation, on the one hand, and the implications of ensuring harmonization and consistencyin multilingual legal texts through institutional translation, on the other. These endeavors are compounded by the significant hybridity and polysemy of legal terminology, as multiple intersections co-exist between legal orders, legal fields and other specialized domains, and between legal and general language. As illustrated by this special issue, corpus-based methodologies have proven particularly fruitful approaches to investigating these issues. They support the description of terminological and phraseological features of legal genres, as well as the acceptability analysis required to make translation decisions and to elaborate lexicographical resources in line with legal and institutional translators' needs.