We propose a Universal Information Sharing and Searching (UISS) system that has a loosely coupled multi-cluster P2P architecture based on Web Service standard technology. It provides a P2P group information sharing and searching services between Special Internet Groups (SIGs), and scalable and fault-tolerant group-sharing P2P Web services with standardized service interfaces and message protocols. We introduce the overall architecture of the UISS system with GISS (Group Information Sharing and Searching) server components. We show three levels of information sharing in the UISS system: a simple case of information sharing within a group, intra-cluster information between tightly collaborated groups, and inter-cluster sharing between loosely cooperated clusters.