Investment arbitration has emerged from modest beginnings and matured into an established presence in international law. However, in recent years it has drifted from the reciprocal vision of its founders. This volume serves as a comprehensive guide for those who wish to reform international investment law from within, seeking a return to the mutuality of access that is in arbitration's essence. A detailed toolset is provided for enhancing the access of host States and their nationals to formal resolution mechanisms in foreign investment disputes. It concludes by offering model texts to achieve greater reciprocity and access to justice in the settlement of disputes arising from international investment initiatives. The book will appeal to all those interested in the future of international investment law, including an international audience of scholars, government officials, private sector actors, and private citizens alike, and including diverse constituencies, communities, or collectives of host State nationals.