The conceptual stage of process design is the most crucial component of the overall design process because the decisions made at this phase have a disproportionately large share of impact than later phases. A methodology for the conceptual stage of the chemical process design has been presented in Pohjola et al. 1994a, Pohjola et al. 1994b and Alha and Pohjola 1994, This study aims at testing the design strategy suggested in the methodology, the performance driven design strategy (Pohjola and Alha 1994). A combined method for eliciting expert knowledge from verbal data was developed for constructing a descriptive cognitive model of a design process. The method has its basis in connectionist view of information processing and it utilizes parallel distributed computing (neural networks).