This book presents the outcomes of the 16th International Conference on Axiomatic Design, titled “Axiomatic Design in Sustainability Transitions: Designing for the economy, Society and the Environment,” held in June 2025 at Cardiff University, UK. It brings together interdisciplinary contributions demonstrating how axiomatic design can support sustainable development.Reflecting the conference’s organization around UN SDG clusters, the first part addresses decent work and economic growth (Goal 8), reducing inequalities (Goal 10), and building sustainable cities and communities (Goal 11). The second part focuses on systems that sustain people and ecosystems, including education (Goal 4), clean water and sanitation (Goal 6), and clean energy (Goal 7). The third part examines industry, innovation, and infrastructure (Goal 9) alongside responsible production and consumption (Goal 12).Together, these contributions form a structured blueprint for engaging with sustainability transitions through design.