Rethinking sustainability as a legal concept: from an integration principle to a prioritization principle

International audienceSince it was first presented by the World Commission on Environment and Development in its report, more than four decades ago, sustainable development has become a guiding principle, endorsed by states, international organizations, and civil society alike. Considered to be a strategic concept for shaping the future of the planet, it is defined as a “development that meets the needs of the present without compromising the ability of future generations to meet their own needs”. As a concept, sustainable development aims to reconcile economic growth with environmental protection and social advancement.However, and despite, what appears to be a broad adhesion of all actors to sustainability, it continues to be more rhetoric than fact. Although the exact legal nature of it remains somewhat ambiguous, the notion has undoubtedly penetrated the legal field. Legally sustainable development has been translated into a principle of integration, expressed in the Rio Declaration. Principle 4 states that “in order to achieve sustainable development,environmental protection shall constitute an integral part of the development process and cannot be considered in isolation from it”. However, empirical studies tend to show that real environmental policy integration is difficult, in spite of strong, ambitious, and well-formulated policy objectives to this effect.Thus, as a legal concept, sustainable development remains weak and can rarely be used as a principle to effectively carry out further environmental protection or equity. It is not only difficult to put it into practice but also the very idea that integrating environmental and social considerations into the economic development process is enough to achieve an effectively sustainable society is flawed. Scientific research has shown that such an integrative approach to attain a supposedly possible equilibrium between economic growth, social advancement, and environmental protection would be meaningless unless planetary limits are taken into consideration.This proposal aims to redefine sustainable development as a concept that can be used effectively by policymakers in order to achieve a balance between environmental protection and socio-economic development. By bringing in and linking it to the notion of planetary boundaries, it creates an avenue well worth exploring to increase the concept’s efficiency and further determine how it can be used as a principle of prioritization rather than that of integration