Identification and application of requirements and their impact on the design process: a protocol study

Establishing requirements is critical in designing, and therefore a central issue of design research. This article reports an empirical study, based on real-time protocol data about the design processes of four, experienced, individual designers, of how requirements get identified, clarified, and used in the design process, and how these influence the quality of its outcome - the emergent design. This is done by first identifying the activities and methods used by designers to identify and apply requirements during designing, and then investigating how these activities and methods relate to the success or failure of the eventual designs in terms of their degree of fulfilment of the requirements. The results indicate that the quality of the activities and methods used has a strong impact on the quality of the emergent design in terms of its degree of fulfilment of requirements, forming a basis for development of guidelines for effective requirement identification and application.