Noelle Riza D. Castillo is the Director of the Space Policy, Legal Affairs an International Cooperation Bureau (SPICB) of the Philippine Space Agency (PhilSA).  She represents the Philippines in international conferences such as the UN Committee on Peaceful Uses of Outer Space (COPUOS), the Asia Pacific Regional Space Agency Forum (APRSAF). She also actively participates in conferences on space security such as the UN Open Ended Working Group (OEWG) on reducing space threats through norms, rules, and principles of responsible behaviors.  She was a member of the most recent 2023-2024 UN Group of Governmental Experts (GGE) on further measures for the Prevention of an Arms Race in Space (PAROS) which submitted its report that recommended substantial elements of an international legally binding instrument on space security.