This book gathers the proceedings of the INPUT2023 Conference on ‘Innovation in Urban and Regional Planning.’ The 12th International Conference INPUT was held at the University of L'Aquila, Italy, on September 6–8, 2023, and brought together international scholars in the fields of planning, civil engineering and architecture, ecology, and social science, to strengthen the knowledge on nature-based solutions and to enhance the implementation and replication of these solutions in different contexts. The book represents the state of the art of modeling and computational approaches to innovations in urban and regional planning, with a transdisciplinary and borderless character to address the complexity of contemporary socio-ecological systems and following a practice-oriented and problem-solving approach. Computational tools, technologies, data, mathematical models, and decision support tools are explored for providing innovative spatial planning modeling methodologies.