Managing cross-store relationships to data objects is disclosed. Specifically, cross-store relationships to data objects stored in a potentially dynamically changing set of persistent data stores is provided through a relationship definition that identifies a type of object to which the relationship pertains and specifies a property to be used to determine, which, if any, objects of the identified type are to be included in the relationship; by determining dynamically which, if any, currently available objects of the identified type have the specified property; and making available from among the objects of the identified type available at that time, if any, those objects, if any, that have the specified property.