This paper discusses some of the implications of introducing the dynamic object role concept into object-oriented metamodels on both implementational and conceptual modeling levels in a coordinated way. The notion is expected to become one of the most fundamental constructs of an object data model and our research concerning object query languages allows us to state that it can be cleanly incorporated into existing object models. On the other hand the total cost of introducing the new notion needs to be considered. Thus, in this paper we look for a lightweight way of introducing object roles, depending as far as possible on already existing and popular concepts. Looking at the issue from the object database point of view, we discuss the necessary extensions and emphasize the importance of direct support of implemented notions from the means of conceptual modeling.