This work presents some of the most recent research results that apply fuzzy sets to engineering design and configuration problems. These chapters cover the representation and manipulation of imprecise information during the synthesis of new designs and selection of configurations. The authors utilize the mathematics of fuzzy sets to represent information that has not yet been reduced to precise descriptions. In most cases, the mathematics of probability is also used to represent more traditional stochastic uncertainties such as uncontrolled manufacturing variations, etc. Presentations on fuzzy optimization and AHP methods are also included. These (fuzzy) set-based methods have particular application to concurrent engineering techniques.