Virtual Worlds (VWs) and other Massively Multi-Party Online Applications (MMOs) are of increasing interest to the Internet community. Innumerable examples exist of such applications, most using proprietary protocols. With their roots in games and social interaction, Virtual Worlds are now being used increasingly in business, education and information exchange. With a growing user base, creators of such systems are interested in developing a standard virtual worlds protocol to enable interoperability. The objective of the OGPX working group is to provide an application-layer wire protocol for Virtual Worlds to a) enable interoperability between applications, b) provide for access and exchange with other systems on the internet such as web services, e-mail and other information storage systems, c) allow network layers to recognize VW traffic and make routing decisions based on its characteristics. The Open Grid Protocol (OGP) describes semantics and protocol interaction for the virtual world, independent of transport, though bindings for carrying OGP over HTTP are defined. The core work of the group will be the production of the Open Grid Protocol suite (OGP), a set of application protocols to communicate and interact with the state of Virtual World applications. The Open Grid Protocol defines virtual worlds with the following assumptions: the Virtual World exists independent of the participating clients users have a single, unique presence in the virtual world the virtual world contains persistent objects the virtual world may be partitioned presence, state and simulation occur on authoritative hosts Foundational components of the Open Grid Protocol include the publication of: 1) the LLSD dynamic structured data system; an abstract type system for representing application layer objects along with serialization rules for protocol messages between these objects. 2) OGP Base, a messaging abstraction to support the unique needs of VW interactions. 3) Guidelines for using OAuth and PKIX compliant X.509 infrastructure to authenticate protocol endpoints. The Open Grid Protocol makes use, wherever possible, of existing, established standards. The OGPX working group is not proposing the standardization of any one complete proprietary protocol, but to build on existing OGP related internet drafts: LLSD Dynamic Structure Data Open Grid Protocol : Base Open Grid Protocol : Authentication An additional deliverable describes the use of how OAuth or PKIX compliant digital certificates may be used with TLS to provide origin integrity in inter-host protocol interactions. Another deliverable is the specification for presence establishment in the virtual world based on the previous "OGP : Teleport" draft of the second life architecture working group.