This article discusses the administration of investor-state arbitration by ICC. Using a study of 33 treaty-based ICC arbitrations as a point of departure - as well as a number of cases where ICC acted as appointing authority for arbitrations conducted under other rules - the article looks at areas of procedure where the ICC Court has developed special practices for treaty-based cases. These include the fixing of the place of arbitration, the preliminary screening of jurisdictional objections, the availability of emergency arbitration, the constitution of arbitral tribunals, and the exercise of its role as appointing authority. Although the vast majority of cases at ICC are based on contracts, the number of investor-state cases is on the rise. The flexibility of the ICC Rules makes them equally suited to this type of arbitration.