This report presents the results of a collaboration between members of the IMLS Digital Collections and Content (DCC) project and developers of the Europeana Data Model (EDM) to construct a formal extension of EDM that explicitly accommodates representation of collections and collection/item relationships. The goal is to enhance the representation facilities of EDM, and to make EDM conducive to representing collection-level data from DCC and other digital content providers. Here we report on the outcomes of the collaboration – use cases, requirements, and recommendations for modeling collections in exchange and aggregation environments – prefaced by a short section covering background on the foundational DCC and Europeana initiatives and an overview of related work in the field