Actinide materials, which are the backbone of nuclear energy, are being examined with growing interest due to the pressing need for carbon-free energy production. Prospects for advanced fuels for next-generation reactors demand a solid understanding of the physical properties of actinide materials, including thermodynamics and quantum mechanics. In this issue of MRS Bulletin, six articles give a broad overview of the current state of actinide science, illustrating current advances and emerging areas of interest in this class of materials, and how this fundamental understanding supports nuclear energy.