In the European Union, legal discourses involve an unprecedented degree of mediation by translators and filtering through 24 official languages. Combined with a complex array of institutional, political, procedural and supranational factors, it results in an emergence of “Europeanized” parallel varieties of national legal languages—hybrids known as Eurolects. Eurolects have developed a distinct supranational terminology, as well as stylistic and grammatical features, which depart from certain conventions of national languages. With the advent of corpus methods, it has recently become possible to explore the nature of Eurolects empirically on a large scale. This chapter overviews corpus studies into Eurolects, focusing on the development of the idea of Eurolects and their “textual fit” to domestic nontranslated varieties of legal languages.