A system and method of simultaneous collaboration is described. The described systems and methods can work with virtually any document structure and do not require advance locking. A plurality of possibly hierarchical, possibly overlapping domains within the document structure is defined. The server handling the simultaneous collaboration requests must keep track of conflicts in edits using the domain information and inform clients whether the edits have been accepted or rejected based on whether or not the edits cause conflicts. A well-designed domain structure as described will avoid conflicts.