Fission energy is currently the largest source of zero-carbon electrical power in the United States, but expanded use has stalled due to high construction costs, long schedules, and lack of policies that credit the low carbon emissions from nuclear power.  This talk will broadly review questions relevant to the future use of fission power, including challenges to achieving deep decarbonization without nuclear, cost drivers for fission energy, options for advanced reactor technology, and management of nuclear wastes.