The paper presents an attempt of real, industrial, engineering knowledge modeling, used in a small company. The authors concentrate on the concept of personal/team knowledge repositories and tools which can support conceptual design. The performance of engineering design tasks usually concentrates on two types of activities: activities connected with modeling the reality, activities analysing the models of reality and associated decision-making actions. Both types of activities are normally fulfilled and integrated by the designers. In doing so, the applied models can be at different levels of complexity, starting from very simple ones, which are based on a few formulae to huge systems of equations. Problems of a high degree of complexity are mostly solved in collaboration with other designers. All activities mentioned above require engineering knowledge which is the result of education and professional experience. The designer is able to operate actively with his knowledge. The knowledge can be the result of reflection on past tasks which he recalls. In many cases, especially in conceptual design, this is a kind of evolutionary progress in a selected knowledge development. In the paper the authors concentrate on the conceptual design, its functioning, its personal/team knowledge development/evolution contexts, its knowledge background and knowledge roots. The whole approach was created and verified in a real industrial design office. The introduced software solutions allow to perform, acquire and support key steps which are necessary to achieve the final conceptual goals.