The International Centre for Settlement of Investment Disputes (ICSID or ‘the Centre') is amending the Rules and Regulations under the ICSID Convention and Additional Facility. These are the most widely used procedural rules in investor-State dispute settlement. It marks the fourth time the ICSID Rules have been updated, and is expected to result in the most comprehensive changes to date. The process has involved extensive consultation with the 154 Member States to the ICSID Convention, the legal profession and the public. ICSID working papers published in August 2018 and March 2019 proposed specific textual changes to the rules, and have formed the basis for discussion and input from stakeholders. Ultimately, a package of amendments is expected to be tabled before the ICSID Administrative Council (the Centre’s governing body) in 2019 or 2020.