Abstract: Requirements uncertainty is recognized as a major source of risk to software development process. A new idea about software development, called the adaptive software architecture design, was proposed in this paper, which offers a feasible way to guarantee the quality of software product during the life-cycle. Firstly, the concept of requirement uncertainty was defined;its causes and impacts were discussed. Secondly, the relationship between the software requirement and the software architecture was analyzed, and the adaptive software architecture approach ws put forth to handle the variable users' requirements and control process risks. Finally, the evolution process of software architecture was characterized with regard to the requirements uncertainty, and a collaborative modeling method was presented to achieve adaptive design between requirements and architecture.

Key words: Requirements uncertainty, Software architecture, Adaptive design, System evolution