Collaborative work at Princeton aims at both the development of currently known materials and the discovery of new materials systems to realize the next generation of quantum computing, sensing, and network technologies. The interdisciplinary environment at Princeton enables close collaboration among experimentalists, engineers, and theorists to accelerate materials optimization and discovery for quantum information science by directing materials development through a feedback loop involving theory, materials growth and engineering, and quantum device measurements, focusing on microscopic mechanisms for decoherence and loss, to allow for rational design and directed improvements in materials.