Bringing together a collection of perspectives from contributors working across multiple fields, the chapters explore the relevance and applicability of international law to particular sectors and issues implicated in development activities. This includes chapters on human rights, gender equality, race and discrimination, environmental law and climate change, forced displacement and migration, and international trade and investment. They analyse how international law rules and processes can influence procedural and substantive aspects of development policies as these regulate various forms of financial support, trade, technical assistance, and policy dialogue. They also explore whether, and how, development could be more effective and yield more equitable and sustainable outcomes if the relevant and applicable rules of international law were better understood, consistently incorporated, and appropriately applied to development activities. A foundational premise of this book is that development policy and practice should be grounded more systematically in international law, rejecting the notion that development law and policy comprise a 'self-contained' regime or that development is undertaken in a legal vacuum. The proposed systematic grounding in public international law would in turn help uphold international legal accountability in the context of development activities.