System Intergration (SI) has resently been conceived as one df the most important tools for enforciong and reinforcing the competitiveness of an enterprise. A major concern of SI lies in sharing many types of information, such as engineering, production, finance, marketing, and so on. Product Data Management (PDM) systems are mainly concerned with product- related information, and also support a large portion of the Commerce At Light Speed (CALS) straitegy. PDM systems receive a great amount df attention form industry, A variety of PDM solutions have been introduced for the last few years, and its market has expanded very fast with an annual growth of 30%. However, in general, it is not an easy task to choose a right PDM solution for a particular company. A major purpose of this paper is to provide essential factors in evaluating PDM systems. While developing the factors. we consider the expected future trend of PDM technologies and three types of PDM-based intergration (frontward, rearward, and sideward integrations). We Propose to carry out the evaluation process in two fold. An overall evaluation is performed first to narrow down many alternatives into a few candidate systems, and then a detailed technical evaluation step follows to determine the final solution. A number of influencing factors are categorized and described in each of these steps.