operation (whether it be a building, manufacturing process, or other complex arrangement of assets) additional changes are made to the environment. In some cases, the differences are small, but they can rapidly accumulate to become significant. CAD models tend to be static. They are rarely updated unless the plant undertakes significant new construction, because the effort, and complexity of most CAD tools don’t make light work of this task. In contrast, Operational 3D Digital Twins are designed to allow for frequent changes, to enable the model to span many types of equipment from various OEMs, and to connect to many operational systems of record. In short, they are flexible, dynamic – an Active model, that lives alongside of the operation it is mirroring.