This book constitutes the refereed proceedings of the 15th International Conference on Model Driven Engineering Languages and Systems, MODELS 2012, held in Innsbruck, Austria, in September/October 2012. The 50 papers presented in this volume were carefully reviewed and selected from a total of 181 submissions. They are organized in topical sections named, metamodels and domain specific modeling, models at runtime, model management, modeling methods and tools, consistency analysis, software product lines, foundations of modeling, static analysis techniques, model testing and simulation, model transformation, model matching, tracing and synchronization, modeling practices and experience, and model analysis.