The Object Management Group' (the consortium that issues the Common Object Request Broker Architecture (CORBA(r)) and Unified Modeling Language' standards) is making the transition from a standards architecture in which only interface definitions are normative to one in which the model is the primary normative artifact. This paper discusses the impact of this move for standards-based interoperability, technological change, reuse, and the state of the practice of application integration. Most significantly, the Model-Driven Architecture' represents an opportunity for users of standards and standards workers, in the Object Management Group and elsewhere, to protect their investments of time, capital, and expertise to a greater extent than was previously possible.