This lecture introduces the complexities of design, emphasizing the ill-posed nature of problems and the existence of multiple solutions. It delves into the challenges of design theory, the competences required, and the pedagogical objectives. The lecture covers the iterative design process, the importance of establishing detailed specifications, and the methodology to approach open solution problems. It also explores the process of problem definition, the types of design, and the phases of the design process. The lecture concludes with a focus on the power of functions, common pitfalls in defining functions, and the deliverables and grading criteria for the course.