The main objective of this study is to contribute to multilingual discourse research by employing ISO-24617 Part 8
(Semantic Relations in Discourse, Core Annotation Schema - DR-core) for annotating discourse relations. Centering
around a parallel discourse relations corpus that includes English, Polish, and European Portuguese, we initiate one
of the few ISO-based comparative analyses through a multilingual corpus that aligns discourse relations across these
languages. In this paper, we discuss the project's contributions, including the annotated corpus, research findings,
and statistics related to the use of discourse relations. The paper further discusses the challenges encountered
in complying with the ISO standard, such as defining the scope of arguments and annotating specific relation
types like Expansion. Our findings highlight the necessity for clearer definitions of certain discourse relations and
more precise guidelines for argument spans, especially concerning the inclusion of connectives. Additionally, the
study underscores the importance of ongoing collaborative efforts to broaden the inclusion of languages and more
comprehensive datasets, with the objective of widening the reach of ISO-guided multilingual discourse research