Anjorin, AnthonySaller, KarstenLochau, MalteSchürr, AndyAßmann, UweDemuth, BirgitSpitta, ThorstenPüschel, GeorgKaiser, Ronny2017-06-302017-06-302015978-3-88579-633-6A Triple Graph Grammar (TGG) is a set of declarative rules describing how consistent triples of graph structures in a source, target, and correspondence domain are to be generated. This generative and high-level specification of consistency can be automatically operationalized and used to derive model generators for test case generation, forward and backward translators, and incremental model synchronizers. As with any domain specific language, a means to modularize TGG specifications is an important requirement, especially for practical applications. We formalized an extended concept of rule refinement for TGGs in previous work and now report on our experience from using rule refinements intensively in a recent industrial project.enText/Conference Paper1617-5468