||This paper discusses the requirements and a methodology for developing,implementing, and possibly standardizing, an extensible set of common messagebasedprotocols for exchanging project-specific and industry-wide informationbased on the IFC data model. The protocols define the syntax and semantics ofvarious data exchange messages in the context of AEC/FM projects. Theinteroperability protocols will achieve two goals: enabling project roles andapplications to exchange information in a consistent and standard manner; andenabling the full or partial automation of a set of project workflow processes. Theprotocols aim to enable heterogeneous and distributed AEC/FM systems toexchange information, within or across organizational boundaries, across allproject phases. Interoperability protocols would include transactions for requestingor querying information from various data sources, exchanging design orconstruction data related to a specific project, exchanging data related to a specificbusiness transaction (e.g. purchase orders), distributing updated projectinformation to project teams, or requesting the execution of specific operations.Formalization and standardization of data exchange protocols between variousproject roles and applications will potentially provide better communication,increased quality, productivity, and reduced costs, delays, and contractual disputes.