Graph Rewriting and Transformation (GReAT) is a Model Transformation Language (MTL) for Model Integrated Computing available in the GME environment. GReAT has a rich pattern specification sublanguage, a graph transformation sublanguage and a high level control-flow sublanguage. It has been designed to address the specific needs of the model transformation area. The GME environment is an example of a Model Driven Engineering (MDE) framework.