An analysis is given in this paper for definition of features of environment adaptive model objects having the capability of description of mutual effects of engineering objects inside and associative engineering objects from the outside world. The final aim of the research is development of environment adaptive model objects for integration in or communication with product models. The model objects, targeted by the reported research, are able to carry and interpret all information and knowledge necessary for their processing. Creation and application of objects during engineering decision procedures as well as revision of earlier decisions during development of products are considered. This paper discusses concepts and features of intelligent model objects as they applied for environment-active modeling. It also reports an analysis of effects of changes in the model environment on model of intelligent engineering object. Following this, paper explains relationships within model objects for the purpose of engineering activities in mechanical systems. Finally, some considerations about implementation of the proposed modeling are concluded.