This paper aims to analyze the concept of equivalence which is registered within the specialized context of the European Union institutions. Firstly, a historical sketch of the principal theories about equivalence is provided in order to studying the said concept from three different perspectives, namely, linguistics -the study of this concept in relation to multilingualism policy-, legal -the relevance of the legal and institutional framework according to this concept of equivalence-, and finally, a perspective from the translation studies to investigate the notions of ST and TT as well as the act of linguistic translation it-self; between other aspects related to translating in this specialized field. Finally, this work aims to provide a proposed definition for the said concept of equivalence by considering the conclusions from the previous issues, considered as limits defining this context of specialization.