Today's organizations (e.g. enterprise, government agencies, libraries, \"Smart\" home) raise increasing needs for information sharing via on-demand information access. An Information Brokering System (IBS) is a peer-to-peer overlay network that comprises diverse data servers and brokering components helping client queries locate the data server(s). Peer-To-Peer (P2P) systems are gaining increasing popularity as a scalable means to share data among a large number of autonomous nodes. The authors study the privacy in privacy-preserving information brokering in distributed information sharing through an innovative automaton segmentation scheme and query segment encryption and data management issues for processing XML data in a p2p setting, namely indexing, replication and query routing and processing.