Due to company mergers, acquisition and business to business interoperability, there is a need for model transformations in the area of business process modeling to facilitate scenarios like model translation, integration and synchronization. Thus this paper concentrates on transformations of models between different business process modeling languages. As current transformation languages provide general solutions and do not support the special properties of business process models, it is still a challenge defining such transformations. To tackle this problem we introduce the model morphing approach. Our main idea is to create an integrated metamodel containing all concepts of the languages of a given domain. Based on this integration the model transformation can be defined in terms of morphing steps. Our approach is demonstrated by model transformation in the area of business process modeling but is generally suitable for domains in which a variety of languages is used that express similar concepts.