1. At a computer system including a processor and a memory, in a computer networking environment including a plurality of computing systems, a computer-implemented method for synchronizing scopes between a source database and a target database without the target database specifying each scope that is to be synchronized, the method comprising: an act of a source database receiving from a target database a synchronization scopes policy corresponding to scope criteria provided by the target database, the synchronization scopes policy including both the scope criteria and a version identifier that together identify at least one of a point-in-time snapshot of a set of scopes meeting the scope criteria as of a latest synchronization, and an empty set of scopes if no previous synchronization has occurred, wherein changes to data in a given scope are synchronized differently based on which point-in-time snapshots the scope is a member of; an act of the source database resolving the set of scopes last synchronized from the source database to the target database based on the point-in-time snapshot of the set of scopes that matched the synchronization scopes policy's scope criteria and version identifier; an act of the source database synchronizing to the target database one or more changes to data in the resolved set of scopes based on which scopes were part of the point-in-time snapshot; an act of sending an updated synchronization scopes policy to the target database upon completion of the synchronization of the source database to the target database; and an act of supplying the updated synchronization scopes policy as an input to a subsequent synchronization.