The paper deals primarily with the classification of what is known in LSP as ‘legal language’. Despite considerable consensus concerning the topics included under this label, there is a substantial amount of terminological uncertainty. An analysis of the use of terms such as ‘variety’. ‘genre’, ‘register’ and ‘discourse’ clarifies the issues that are prevalent in works on legal language. Such an analysis may also clarify issues in LSP in general, for this is relevant to medical, engineering, and any other professional language. The term ‘legal discourse’, it is argued, is the most accurate term to describe the phenomenon under discussion, since not only does it include legal register, but it involves the various legal genres, too. In fact, legal register as such, in terms of special words and expressions, may be of secondary importance today, even in LSP teaching, and any study of legal discourse should perhaps become mainly a study of legal genres.