What is it about international arbitration that makes it so open to evolution and adaptation? What are the main pressure points today and the unmet needs of stakeholders? What are the opportunities for expansion to new sectors and new audiences? What are the drivers for change, the obstacles and the risks? And equally important, what are the core principles that should never be lost? These were the topics of the Twenty-Fourth ICCA Congress, held in Sydney, Australia, in April 2018, the proceedings of which are collected in this volume. The volume highlights arbitration as a ‘living organism’ that has adapted in the past to various challenges, and that today – under attack from various quarters – might need to demonstrate its adaptability again. Accordingly, the contributions address the evolving needs of users, the impact of the rapidly changing face of technology, the expectations of the public, and the convergence and divergence of different aspects of legal traditions and cultures. Topical issues of interest for practitioners, academics, and students of arbitration include the following: legitimacy and authority of arbitrators, institutions and professional organizations to act as lawmakers; investment treaty reform, with particular reference to the definition of ‘investment,’ the evolution of substantive treaty standards, and sustainable development obligations; commercial arbitration reform, including issues of public and private interest, the development of common law, and cost, delay and transparency concerns; revisiting party autonomy in choosing decision-makers, including through institutional appointments or investment courts; equality of arms, the economics of access, and the role of costs and third-party funding; public-private disputes and special issues that arise when State entities arbitrate; public participation and transparency, and their effect on both ISDS and commercial arbitration; revisiting conventional wisdom in organizing arbitral proceedings; lessons to be learned from other dispute resolution frameworks; technology as friend and enemy, including new tools, new threats, and cybersecurity; arbitration of disputes in conflict and post-conflict zones; inter-generational blame and praise in investment arbitration; and the emergence of sovereign wealth funds as arbitration participants. A special section on ‘New Frontiers in Arbitration’ offers enlightening perspectives on new types of claims and new types of stakeholders likely to affect the future of international arbitration, including the potential for climate change disputes and enlarged participation.