Collaborative Data Sharing raises a fundamental issue in distributed systems. Several strategies have been proposed for making shared data consistent between peers in such a way that the shared part of their local data become equal. Most of the proposals rely on state-based semantics. But this suffers from a lack of descriptiveness in conflict-free features of synchronization required for flexible network connections. Recent applications tend to use non-permanent connection with mobile devices or allow temporary breakaways from the system, for example. To settle ourselves in conflict-free data sharing, we propose a novel scheme "Operation-based Collaborative Data Sharing" that enables conflict-free strategies for synchronization based on operational semantics.