The One Health approach is increasingly recognised as a holistic solution to complex global health and ecological challenges. Legislation is of utmost relevance for its effective implementation, providing a mechanism to institutionalise intersectoral and interdisciplinary collaboration, clarify responsibilities, and promote sustainability. However, the legal nature of One Health remains underexplored.

This paper examines how the key underlying principles of One Health align with legal principles and concepts broadly recognised by legal literature and jurisprudence, including those articulated in the Rio Declaration and the International Law Association’s New Delhi Declaration on principles of international law relating to sustainable development. Emphasis is placed on the principle of integration, a cornerstone of sustainable development that offers a pathway to operationalize One Health within legal frameworks.

By conceptualizing One Health as an extension and practical application of the principle of integration, this paper advances its characterisation as a legal concept, embedding it within broader principles of international law. One Health is positioned as a legal construct, providing a pathway for its implementation through law and affirming its role as an integral component of sustainable development.