For several decades, the social and environmental consequences of the capitalist production model have given rise to the emergence of supranational organisations and commissions such as the World Commission of Environment and Development, the Sustainable Development Commission of the United Nations, Earth Summit, and so on. These organisations study the effects of economic change and promote new production types which manage resources and are concerned with balance. Sustainable development is considered a call for change and has imposed itself on any reflection about the relationship of man to his material and social environment. If we take these new principles of public action into account, it is important to see how they put pre-existing agendas about area development, and especially landscape policies, to the test. What is the social understanding, the landscape professional knowledge and the practical actions needed to take these new principles into consideration and integrate them into practice? This question is asked in a context where landscapers, due to their position in area development policies and the range of competences which they have, are in a good position to extend or deepen their knowledge in relation to this new angle.