Our research is focused on the emergent behavior of quantum materials, especially those with strong electron correlations that exhibit unconventional superconductivity and other broken symmetry phases. We investigate the electronic behavior through magnetic resonance of both nuclear spins and color centers in diamond. These spins are natural quantum sensors, and provide detailed information about the local static and dynamic properties of their environment. We are particularly interested in quantum materials that exhibit strong correlations and how these evolve at cryogenic temperatures, high magnetic fields, large hydrostatic pressures, and uniaxial strain. We utilize both conventional induction-based and optically-detected magnetic resonance, operate at frequencies up to several gigaHertz. Our work has potential impact in a variety of directions, including novel materials for future quantum computers, a future superconductor-based electric power grid, and quantum information technologies.