Social effectiveness and the right to an ecologically balanced environment have been threatened by the drive for development, especially in the agribusiness sector. Agricultural fronts are being opened up to the detriment of natural vegetation, only to be resisted by environmental laws. The purpose of the Legal Reserve institute is to modernise the right to property. The aim is to find out what changes it has undergone with the advent of the new Brazilian Environmental Law and what criteria have been adopted to implement these changes, as well as investigating their consequences for the environment. Finally, sustainable development must be sought in order to achieve progress for the current generation without jeopardising the development of future generations, balancing both interests.