The PCA has modern and multifaceted institutional mechanisms to settle international
disputes in a peaceful manner. The Optional Rules for Arbitration of disputes Relating to
Natural Resources and/or Environment provide for the establishment of specialized panels
of arbitrators. The rules also provide for the establishment of lists of scientific and technical
experts who may be appointed as expert witnesses. It is optional for the parties to a dispute
to choose the arbitrators, conciliators, or expert witnesses from these lists (PCA), ‘Panels of
Arbitrators and Experts for Environmental Disputes'. The PCA is currently acting as a registry in four inter-state proceedings, 105 investor–state arbitrations, and sixty-five cases under contracts or other agreements involving a state or public entity. This study has discussed the cases relating to the environment and natural resources from January to December 2022.