Huge Simulink controller models often consists of (almost) identical subsystems, very often resulting from copy-and-paste operations and only slight adaptation of the subsystems by the model engineer. Although this “copy-and-paste” approach might help to achieve initial results very fast, in the long-run such subsystem clones can create considerable problems. Like code clones, model clones increase the effort for testing and maintenance. Model clones also tend to influence the code efficiency and code quality in a negative way in case the Simulink model is used as a basis for code generation. JUST SIMPLIFY is an approach for detecting model clones in a Simulink model automatically based on model metrics calculations. This approach has been implemented in our model metrics and complexity measurement tool M-XRAY. JUST SIMPLIFY allows reducing the effort for model refactoring by avoiding time consuming manual search for model clones. As a result, the effort for testing and for maintaining models can be reduced and the code quality can be improved significantly.