Designing systems-oriented products is challenging because of the broad scope of the task. Design teams must integrate various solution elements, such as hardware, software, service, and infrastructure, while resolving the communication challenges among different domain experts and stakeholders. Adding to the complexity of systems design is the unclear and ambiguous project scope at the beginning. I defined there two attributes as "amorphous."

This research departs from the observation of 32 industry-sponsored projects that used the Design for X curriculum at Stanford University. I found that, at the onset of open-ended projects that are systems-oriented, design teams struggled because they knew fewer than 4 of the 6 W's (Who, What, Where, When, Why, How). They did not have detailed functional or structural specifications, as is the case with hardware or software products. Furthermore, there were no systematic and simple approaches that guided design teams from envisioning unknown market needs to defining functional requirements. Only when they reached the functional requirements phase were they able to use well-established engineering design methods.

This research proposes Scenario-based Amorphous Design (SAD) to bridge the gap between the vague needs-finding phase and the rigorous engineering design phase. It does so by enabling design teams to effectively deal with ambiguity and to communicate their ideas to different domain experts as well as with customers and managers—and to do so through a common language—the scenario, which is defined as a set of Who, What, Where and When.

This dissertation is based on case studies from the healthcare industry and the high-tech industry which demonstrate how multidisciplinary design teams used SAD methods to extract functions and requirements from under-defined project scopes using scenarios. Based on cognitive psychology, SAD methods such as Scenario Graph and Scenario Menu helped the teams envision and organize potential markets. Scenario Prototyping Rapidly aided them in generating insights, testing their concepts, and interacting with their stakeholders, yielding a Service Fishbone Diagram for analyzing use-cases. Dynamic-Customer Value Chain Analysis helped the teams simulate and implement their new business model over a technological roadmap. The integrated framework of SAD guided the design teams in visualizing and organizing scenarios and making decisions in order to define an amorphous system.

Today, Stanford University in the United States and Keio University in Japan have adapted SAD in their capstone design curriculum. Furthermore, more than 30 design teams around the world have successfully applied Scenario-based Amorphous Design (SAD) to their amorphous systems-oriented projects. I have validated the effectiveness of SAD qualitatively using interviews, and quantitatively using statistical methods and method votes.