The aging of software is a lingering problem for many companies. We know that in new projects, Model Driven Engineering can be used to prevent this aging in the future. However, this does not solve the problems we have today with legacy information systems. We propose a general method for the modernization of legacy information systems, by transforming these systems into model driven systems. To accomplish a transformation into a model driven system, first a model is extracted from the legacy system. This model is then transformed into a model driven system, using Model Driven Engineering. The method is not limited to the data-model of the legacy system, but is applicable to the entire system. It has a best-effort character, and allows for automatic traceability. All these properties are validated with the Thinkwise Software Factory. Thinkwise Software develops technical innovations to create smart software applications. These applications are self-learning, easy to use and have an unlimited life expectancy. At the time of writing, the techniques discussed in this work are implemented further at Thinkwise, and have proven their effectiveness in several customer projects.