similar cases will be treated similarly.16 Urban planning is more than anything unequal, but this inequality must be justified during the planning process and compensated when is executed to make effective the superior principle of equality.17 Participation The decisions should be explained intelligibly by the provision of reasons so that persons affected by the decision, and perhaps the wider community, will know why it has been made. Absent intelligibility in the decision, the first four standards of legality, rationality, proportionality and fairness may be of diminished practical effect because the capacity to judge compliance with them and to seek review will be compromised.18 Participation is especially relevant when zoning and planning involves indigenous communities or minorities. For instance, in Australia native title rights and interests are recognized by the common law and are in part protected by the Racial Discrimination Act.19 This means that every planning decision must take into account the rights and interests of the indigenous communities that are going to be affected, and that these communities must be consulted. Sustainable Development At the heart of this principle is the idea of ensuring a better quality of life for everyone, in the present and in the future.20 The United Nations defines Sustainable Development as, “Development that meets the needs of the present without compromising the ability of future generations to meet their own needs.”21 Sustainable development is central to the economic, environmental and social success of any country and in recent years it has become the core principle underpinning planning worldwide. Sustainable development has three overall goals: to meet the present and future physical and social needs of the residents; to meet their economic needs and enable economic growth; and to protect the ecosystem. Sustainable 16 Chief Justice Robert French AC, “Property, Planning and Human Rights.” 17 Almudena Fernández Carballal, “Urban qualification and rationality: Concerning the Sports City of Real Madrid Football Club (Calificación urbanística y racionalidad. A propósito de la nueva Ciudad Deportiva del Real Madrid, Club de Fútbol).” 18 Chief Justice Robert French AC, “Property, Planning and Human Rights.” 19 Ibid. 20 The sustainable development commission, Sustainable Communities and Sustainable Development. A Review of the Sustainable Communities Plan. 21 United Nations, Report of the World Commission on Environment and Development. 12