Large models for complex systems can be decomposed in separate pieces corresponding to different perspectives on the system. This decomposition allows the modeller to check properties locally on some aspects of the system before considering the global complexity of the model. In this paper we consider two types of decomposition: according to the concerns identified in the requirements and according to structural and behavioural perspectives. Once the separate models are available and have been checked separately, they have to be composed to check global properties. In this work, we propose automatic composition operators for symmetric and asymmetric concern models, each concern being modelled from a structural and behavioural point of view.