Many potential systems are being studied for 21st Century implementation. Affordability is the key to survival in the aerospace industry, and major reductions in the defense budget are contributing to defense industrial base restructuring. With fewer new business opportunities, companies can maintain a competitive edge only if they are able to make strategic decisions to determine appropriate product lines to pursue for new business opportunities. It is essential to conduct architecture studies to identify viable company products for the defense market as it will exist in ten to twenty years. Market analyses can identify appropriate product lines that impact future business and contribute to company longevity. Defense technologies are rapidly being transferred to the commercial market place where cost competitiveness drives the market. Conversely, the commercial market is having an impact on technological development. Previously, defense firms had the luxury of building technologically advanced, complex, but expensive defense systems. Now it is increasingly likely that companies win contracts due to their ability to deliver cost effective systems. Accurate system architecture life cycle cost assessments are essential, with least expensive design options selected early in the design process. In early architecture study stages most model parameters are difficult to assess with any degree of fidelity. Traditional cost analysis methods are insufficient to evaluate future system architecture costs accurately. Knowledge base models are the wave of the future. With only a few high level input values specified, values for each input parameter derive from industry data. The analyst can insert company specific values where known, and store tailored knowledge bases for similar future company projects. Knowledge bases also facilitate interaction with engineers by presenting a set of input values to critique. Knowledge base models simplify the process of modeling system architectures with no unreasonable loss of accuracy.