Software systems with constrained and dynamic environments need to adapt to local and diverse computing environments by providing highly customized services at run-time. In order to address such dynamic changes effectively, composition models addressing complicated composition issues and supporting advanced composition features are required. In order to analyze and identify the required features of composition models supporting dynamic changes, we propose the dimensions of composition models by survey and analysis of existing work. Based on the dimensions, it is possible to provide a road map to improve capability of a composition model for a specific domain such as a dynamic mobile agent domain.