—This paper presents a massively shared virtual reality system based on a network of peers. It does not rely on any server nor on IP multicast, and intends to be scalable to an unlimited number of participants. Following a peer-to-peer scheme, entities collaborate to build up a common virtual world. The behavior of entities, running algorithms in order to maintain local properties, ensures the consistency of the virtual world and the connexity of the network. The paper also describes how entities join the network and enter the virtual world at a particular position. Keywords— Peer-to-peer System, Shared Virtual Reality, Massively Distributed System, Distributed Algorithms, Self-organizing Systems, Computational Geometry.