The Green Building XML schema, referred to as “gbXML”, was developed to facilitate the transfer of building information stored in CAD building information models, enabling integrated interoperability between building design models and a wide variety of engineering analysis tools and models available today. gbXML has the industry support and wide adoption by the leading CAD vendors and HVAC software vendors. With the development of export and import capabilities in several major engineering modeling tools, gbXML has become a defacto industry standard schema. Its use dramatically streamlines the transfer of building information to and from engineering models, eliminating the need for time consuming plan take-offs. This removes a significant cost barrier to designing resource efficient buildings and specifying associated equipment. It enables building design teams to truly collaborate and realized the potential benefits of Building Information Modeling.