Numerous treaties and other instruments that refer existing or future disputes to arbitration designate the PCA Secretary-General as the appointing authority for the appointment of arbitrators. Typically, the appointing authority is empowered to act when the parties to the dispute fail to constitute an arbitral tribunal within a specified time period following the commencement of the arbitration proceedings.
The PCA may also be charged with providing administrative support to tribunals operating under the respective treaty or instrument, or with making its hearing facilities available to such tribunals. Some instruments provide for arbitration according to one of the sets of procedural rules adopted by the PCA for the conduct of arbitral proceedings, although the PCA is most often called upon to administer arbitrations under the UNCITRAL Rules, or rules that were drafted for the specific dispute.
Instruments referring to the PCA have been concluded between various combinations of states, international organizations, and private parties, and cover subject matter such as investment protection, environmental protection, international development cooperation, and the constitution and operation of international organizations. Examples of these are set forth below.