This paper deals with the development of a Knowledge Based Engineering (KBE) methodology for supporting a manufacturing company, in particular railway manufacturers, in their analyses for reusing existing products in new projects. The proposed methodology is based on the development of a Decision Support System (DSS) and the use of an analysis, called Adopt/Adapt/Innovate (AAI), aimed at identifying products already designed that fully or partly fit what required by new bids. The DSS is built within a PLM software and part of the research concentrated on comparing the PLM suites available in the market searching for the best tool able to act the role of a centralized management dashboard for knowledge reuse. DSS and AAI analysis are the base for future research activities for obtaining a KBE system that automatically models complex railway products starting from the customer requirements, drastically reducing the time to market.