This open access book presents the proceedings of the 17th International Congress of Polymers in Concrete 2023 (ICPIC 2023), held under the theme "Cement-Polymer Composite in Circular Economy". It provides multidisciplinary and contemporary knowledge on the application of polymers both in and on concrete, covering topics from the modification of concrete compositions with modern admixtures and additives to the use of alternative binders and polymer composites for concrete reinforcement. The book also explores improvements in concrete surface properties and special functionalities such as self-healing, self-cleaning, and energy consumption control using Phase Changing Materials (PCM). As the premier global event in this field since 1975, ICPIC continues to drive innovation and sustainability, uniting researchers, academics, industry professionals, and students to advance the future of polymers in concrete.