In the paper we consider the concept of "Strategic Information System" (SIS) which is based on findings of Synnott and other authors. The starting points of SIS were set by C. Wiseman. According to him SIS is an information system designed to support and increase the competitive strength of company. SIS is an information system which is essentially different from the classical definitions of information systems. A critical analysis of modern approach to SIS tells us that these are oriented mainly into searching methodologies. In our work we are trying to connect SIS into engineering system such as Simultaneous Engineering. To manage this we have developed a five level manufacturing model and a five level business model and connect both model together according to strategic information system. These models are developed for small and medium sized companies and is already implemented in tools industry.