Most electricity outages in the United States are localized and do not expand outside of state or regional borders or a utility’s service territory. However, when large parts of the entire electricity system are failing (due to an extreme weather event, a cyber-attack or other natural or man-made hazards), blackstart capable generation resources are crucial to restarting the electricity grid. Blackstart resources can be started without electricity from the main grid, thus providing the initial energy needed to repower the larger electricity grid. Without operational blackstart units, restoration time would be significant and impacts of a large outage severe. This briefing paper for State Energy Offices provides background information on blackstart units and the blackstart process. It highlights the importance of blackstart units and outlines how blackstart units are regulated and the changing considerations for blackstart units as the United States’ electricity grid undergoes a transformation toward more renewable energy and distributed energy resources (DER). The briefing paper concludes with considerations for State Energy Offices for enhancing blackstart capabilities.