This book, composed of two volumes, presents the latest advances, innovations, and applications in fibre-reinforced polymer (FRP) composites and structures, as shared by leading international researchers and engineers at the 12th International Conference on FRP Composites in Civil Engineering (CICE), held in Lisbon, Portugal, on July 14&16, 2025. The volumes cover a broad spectrum of topics, including: all-FRP structures; bond and interfacial behavior; concrete-filled FRP tubular members; FRP-reinforced or pre-stressed concrete structures; confinement; design methodologies and guidelines; durability and long-term performance; fire, impact, and blast resistance; FRP as internal reinforcement; hybrid FRP systems with other materials; new materials and products; seismic retrofitting; structural strengthening of concrete, steel, masonry, and timber; and experimental testing. All contributions underwent an international peer-review process, ensuring both quality and relevance. Together, they provide a rich source of ideas that not only advance current understanding but also inspire new research directions and foster multidisciplinary collaboration across the field.