While well-proved shape description methods are available in present day CAD/CAM systems modeling of design intent is a rather new area. The authors have investigated modeling of complex considerations that are behind the decisions of engineers on model data in the course of product modeling. A product modeling system is considered that involves humans, model creating procedures and model data processing procedures. The proposed intent description can be utilized in present and future applications and later modification or re-engineering of models. Modeling of design intent is considered as part of the virtual manufacturing where integration of conceptualization activities is emphasized. In this paper, the problem and the analyzed human-machine-human system are outlined. Then characteristics and content of the design intent are described. Following this, representation of design intent and attaching intent data to product models are detailed. Finally, possibilities for application of the results of the research in CAD/CAM modeling environments are concluded.