University of Twente is looking for two highly motivated and hardworking PhD candidates to take up these challenges. You will work in a stimulating multidisciplinary scientific environment and in industry. The challenges described require novel scientifically founded approaches, and the approaches need to work in real life. Therefore, you will spend a significant part of your time at our industrial partner where you will be involved in (system) design challenges and decision making. Specifically, you will: 1) Investigate decision making in complex system development. One researcher will look from a technical perspective, the other from an organizational and product portfolio perspective. 2) Develop novel systems engineering and architecting tools, methods and approaches to support in these decision making processes, considering their multidisciplinary nature. 3) Test and evaluate the tools, methods and approaches in a real development environment.