Model integration has been an active field of research. Ideally one would like to apply the same results from software engineering to construct new models from previously defined and tested ones. As in software engineering many algorithms and/or procedures written in different languages are assembled together, so there are many models expressed in different modeling languages which we would like to integrate when necessary. Our aim is to show some new results in model integration, achieved in the framework of structured modeling (SM), by looking only at the model scheme and to investigate the possibility of constructing a unified framework to integrate algebraic and structured models.