ASME has published a new standard (ASME Y14.47) on model-based definition (MBD) organization practices. It is part of ASME’s series of standards on engineering product definition and related documentation practices. ASME Y14.47 introduces novel MBD-element classifications, which are based on industrial recommended practices in organizing and managing three-dimensional geometric models and related information of products. Such classifications form the technical basis for developing information models (e.g., as XML schema definitions) to enable interoperability among engineering information systems in model-based enterprises (MBEs). This paper provides an exposition of these classifications, while emphasizing the need and use of such standardized classifications in modern MBEs.