The Repository Query SOP Class is an extension of the Study Root Query/Retrieve - FIND SOP Class with features that support very large response sets. For queries that might return millions of records, it allows both the SCU and SCP to set constraints on the number of records to be returned in a single C-FIND transaction. It specifies well-defined behavior for a "partially completed" status to be returned if not all entities selected by the key matching Attributes in the request were returned, and allows the SCU to specify a "continuation point" in a subsequent query to return responses from that point onward. This provides a mechanism to "window" through the entries in a deterministic way without overburdening either the SCU or the SCP.