International investment law has long relied on treaties that grant enforceable rights to investors and resolve disputes through adjudication. This model has produced systemic constraints on regulatory autonomy, fragmented legal authority across treaty layers and limited responsiveness to development priorities. A new generation of treaties introduces a different organising logic. Investment facilitation agreements construct treaty obligations around procedural conduct rather than investor protection. Despite their growing prevalence, their legal structure, functional orientation and implications for treaty design remain under-theorised. This article argues that facilitation treaties reconstitute the legal function of investment agreements. They do not modify the protection-based model; they establish a procedural architecture in which treaty obligations operate through administrative performance at the domestic level. The argument is developed through comparative analysis of treaty practice at multiple levels, including the World Trade Organization Investment Facilitation for Development Agreement, the African Continental Free Trade Area Protocol on Investment, the Regional Comprehensive Economic Partnership and a range of second and third-generation bilateral treaties. Six procedural commitments (transparency, administrative coordination, investor support, dispute prevention, capacity-building and sustainability) are identified and theorised as foundational legal elements. The article contributes a general theory of procedural treaty design. It shows how legal ordering across international and domestic systems can be achieved through coordination rather than adjudication, with broader implications for international economic law and the evolution of international legal instruments.