The thesis reviews design methods in general, and emphasizes the understanding of design as a thinking process that depends on designers' experience, and their interaction with the different design activities performed with regard to the environmental settings and contexts. It focuses on building a framework for the description of the architectural design approaches used by experienced architects in practice. After analysing the protocols revealed by twelve experienced architects, the thesis argues that 'scenario-based design' (SBD) is a way of thinking that used by the architects to generate the design solution by means of cognitive matching of technical, functional, contextual, and inspirational criteria throughout the design process. The research finds that the architects primarily use the context constraints that match with the brief requirements to initiate design concepts and generate solutions.