Although the previous World Radiocommunications Conference (WRC-19) attempted to resolve spectrum-sharing issues among the disparate new satellite constellations, issues have multiplied as these constellations are coming into use before all the rules have been created. The upcoming WRC, to be held at the end of 2023, will grapple with spectrum and situational sharing issues among constellations that are larger than ever before, and that are disrupting national regimes designed for licensing more traditional, one-at-a-time geostationary satellites. The agenda for WRC-27 will surely include multiple areas of study related to constellations, and the International Telecommunication Union (ITU) will need to work closely with the UN’s Office of Outer Space Affairs (UNOOSA) to resolve situational issues such as traffic management, debris, and the sustainability of the outer space environment. The emergence of operational constellations is disrupting legal regimes for states and industrial players, and future Agenda Items (AIs) should be added to WRC-27 or future Committee on the Peaceful Uses of Outer Space (COPUOS) sessions.