A development system with methodology for run-time restoration of UML model from program code is described. In one embodiment, for example, in a computer system, an improved method is described for developing and executing an application, the method comprises steps of: creating a model describing business objects and rules of the application; creating source code for the application, including representing the model within the source code itself; compiling the source code into an executable application; running the executable application on a target computer in conjunction with a run-time framework that provides services to the executable application; and while the executable application is running, reconstructing the model from the executable application and making it available to the run-time framework.