This volume collects the inaugural PhD Day proceedings of the Italian Association of Archaeometry (AIAr), successfully hosted on October 2, 2025, at the Enrico Fermi Research Center (CREF) in Rome. This full-day event was a dedicated interdisciplinary forum for scholarly exchange, critical discussion, and professional development within the field of archaeometry and the sciences applied to cultural heritage. These proceedings are designed to provide a comprehensive, state-of-the-art overview of current doctoral research trends. This volume will serve as a reference for researchers, students, conservators, and museums interested in the contemporary status and future directions of Heritage Science. The included research covers a wide range of topics, showing the new and collaborative approach of current PhD projects in Italy.