A protocol for synchronizing data is provided. Additionally, a system and method of using the protocol are also provided. The protocol allows responses to be grouped with commands in a single XML document. It provides a command for requesting a single object be sent without requiring that all unsynchronized objects be sent. It provides a command for specifying how many objects at a time should be sent and a response that indicates that more objects are available to be sent. It provides a means for arbitrarily extending the protocol in application-specific ways. It provides a means for sending updates while requesting that no updates be sent back.