This paper describes a basic study on an emergent design system in which serendipity is exerted from interactions between computer and human. The system is proposed to support idea generation in the early design process. In the early design process, which is composed of conceptual and basic design, new and novel ideas of design should be obtained from global solution search because the design objective and conditions are unclear. Therefore, we propose an emergent design system, which enhances designer's serendipity, intended to support idea generation. Serendipity is a natural ability to unexpectedly make interesting or valuable discoveries. This ability is influenced by designer's experiences and knowledge. The possibility of gen...