Introduction: Dr. Xuening Bai is a theoretical and computational astrophysicist with broad interest in planet formation and high-energy astrophysics. On planet formation, he aims to build the most realistic model of protoplanetary disks (in which planets form), and to explore the physics and chemistry of planet formation under most realistic disk dynamics. On high-energy astrophysics, his research interest includes accretion disks and disk winds, pulsar physics, cosmic-ray acceleration, transport and feedback. Most of his research involves the development and utilization of advanced computational tools, particularly magnetohydrodynamics (fluid) and particle-in-cell (particle) methods, on high-performance computing systems. He has contributed significantly to the Athena MHD code, and is more recently involved in the Athena++ code project.