Ecologically sustainable development (ESD): HSC Legal Studies

What this dot point is asking

The final dot point of the nature of global environmental protection is the importance of ecologically sustainable development: biodiversity, intergenerational equity, intragenerational equity, the precautionary principle. You need to know what ecologically sustainable development (ESD) means, explain each of the four named principles with legal examples, and show why ESD matters: it is the idea that ties international environmental law, Australian legislation and court decisions together, and it gives you criteria for judging whether a response actually protects the environment.

ESD also connects the rest of the option. When you evaluate a legal response to conflict between the demand for resources and environmental protection, or Australia's federal structure, ask whether it conserves biodiversity, treats future generations and poorer communities fairly, and acts with precaution.

The answer

What ESD means and where it came from

In 1987 the World Commission on Environment and Development (chaired by Gro Harlem Brundtland) published Our Common Future, defining sustainable development as "development that meets the needs of the present without compromising the ability of future generations to meet their own needs". The idea reconciled two demands that had been treated as opposites: economic development (especially for poorer countries) and environmental protection.

Australia adopted the idea as ecologically sustainable development, emphasising that the economy depends on healthy ecological systems. The National Strategy for Ecologically Sustainable Development (1992) defined ESD as "using, conserving and enhancing the community's resources so that ecological processes, on which life depends, are maintained, and the total quality of life, now and in the future, can be increased". The same year, the Commonwealth, states and territories signed the Intergovernmental Agreement on the Environment, which set out the ESD principles that now appear in legislation.

In legislation. The principles are listed in the Environment Protection and Biodiversity Conservation Act 1999 (Cth) s 3A: integrating long-term and short-term economic, environmental, social and equitable considerations; the precautionary principle; intergenerational equity; conserving biological diversity and ecological integrity as a fundamental consideration; and improved valuation, pricing and incentive mechanisms. In NSW, the Protection of the Environment Administration Act 1991 (NSW) s 6(2) defines the same core principles, and many NSW Acts adopt that definition. Decision-makers under these Acts must take ESD into account.

Biodiversity

Biological diversity is the variety of life: genetic diversity, species diversity and the diversity of ecosystems. Conserving it matters because ecosystems provide food, clean water, pollination, climate regulation and medicines, because extinction is irreversible, and because many people hold that species have value in themselves. The IPBES Global Assessment (2019) found around 1 million species threatened with extinction.

• International law. The Convention on Biological Diversity (1992) has three objectives: conservation, sustainable use, and fair and equitable sharing of the benefits of genetic resources. It has 196 parties; the United States is the main non-party. The Kunming-Montreal Global Biodiversity Framework (December 2022) sets 23 targets for 2030, including Target 3 ("30 by 30"): effective conservation of at least 30 per cent of land and inland waters and 30 per cent of coastal and marine areas. Species-specific treaties include CITES (1973) on trade in endangered species, the Ramsar Convention (1971) on wetlands and the World Heritage Convention (1972). The High Seas Treaty (in force 2026) extends protection to ocean areas beyond national jurisdiction.
• Australian law. The EPBC Act protects listed threatened species and ecological communities as matters of national environmental significance; in NSW the Biodiversity Conservation Act 2016 (NSW) does the same. Australia has committed to the 30 by 30 target.
• Evaluation. The framework is ambitious, but the Aichi targets that preceded it (2010 to 2020) were not fully met at a global level, and biodiversity loss continues. In Australia, State of the Environment 2021 found the environment "poor and deteriorating".

Intergenerational equity

Intergenerational equity is fairness between generations: the present generation should maintain or enhance the health, diversity and productivity of the environment for the benefit of future generations. Rio Principle 3 states that "the right to development must be fulfilled so as to equitably meet developmental and environmental needs of present and future generations".

Future generations cannot vote, lobby or sue, so the principle depends on institutions that speak for them:

• Minors Oposa v Factoran (Philippines Supreme Court, 1993). Children, represented by their parents, sued on behalf of themselves and "generations yet unborn" to stop timber licences. The Court accepted that they had standing, relying on the Philippine Constitution's right to a balanced and healthful ecology. It is the classic example of a court giving future generations a voice.
• Gray v Minister for Planning [2006] NSWLEC 720. The NSW Land and Environment Court (Pain J) held that the environmental assessment for the Anvil Hill coal mine should have considered the greenhouse gas emissions from burning the coal (scope 3 emissions), applying ESD and intergenerational equity.
• Sharma v Minister for the Environment. In 2021 the Federal Court (Bromberg J) found the federal Environment Minister owed Australian children a duty of care to avoid causing them personal injury from climate change when approving a coal mine extension. In March 2022 the Full Federal Court unanimously overturned that finding ([2022] FCAFC 35), holding that the issues were for Parliament and government policy, not the law of negligence. It shows how hard it is to turn intergenerational equity into enforceable rights in Australian law.
• The ICJ advisory opinion (23 July 2025) treated intergenerational equity as relevant to interpreting states' climate obligations, and stated that the environment is the foundation for the health and well-being of present and future generations.

Intragenerational equity

Intragenerational equity is fairness among people alive today: between wealthy and poorer states, and between groups within a state, so that the costs and benefits of using the environment are shared fairly. The people least responsible for environmental harm, such as low-lying Pacific states or remote communities, often suffer it first.

• Common but differentiated responsibilities. Rio Principle 7 and UNFCCC art 3(1) require parties to protect the climate system "on the basis of equity and in accordance with their common but differentiated responsibilities and respective capabilities". Developed states took on binding targets under Kyoto; under Paris they are expected to lead and provide finance.
• Finance and loss and damage. COP27 (2022) agreed to establish funding for loss and damage, and the fund was operationalised at COP28 (2023). At COP29 (Baku, 2024) parties agreed a new goal of at least USD 300 billion a year by 2035 for developing countries, far below what developing countries sought. At COP30 (Belém, 2025) parties called for efforts to triple adaptation finance by 2035.
• Human rights. In Daniel Billy v Australia (2022) the UN Human Rights Committee found Australia had violated Torres Strait Islanders' rights to private and family life and to enjoy their culture by failing to adapt to climate change. Its views are not binding.
• Climate mobility. The Falepili Union treaty between Australia and Tuvalu (in force 28 August 2024) offers a pathway for up to 280 Tuvaluans a year to live in Australia, recognising that climate change threatens Tuvalu's territory.
• Evaluation. Intragenerational equity is the principle on which developing states say the system has failed them: finance is below need and the largest historical emitters are not bound to pay reparations, although the ICJ (2025) confirmed that breaches of climate obligations can give rise to state responsibility.

The precautionary principle

Rio Declaration Principle 15 states: "Where there are threats of serious or irreversible damage, lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental degradation." It matters because environmental science is often uncertain when decisions must be made, and some harms (extinction, climate tipping points) cannot be undone.

• Leatch v National Parks and Wildlife Service (1993) 81 LGERA 270. Stein J in the NSW Land and Environment Court applied the precautionary principle to refuse a licence to "take or kill" endangered fauna, including the giant burrowing frog, for a proposed road, because the likely impact was uncertain.
• Telstra Corporation Ltd v Hornsby Shire Council [2006] NSWLEC 133. Preston CJ set out the leading Australian test: the principle is triggered by (1) a threat of serious or irreversible environmental damage and (2) a lack of full scientific certainty about it. If both are shown, the burden shifts to the proponent to show the threat is negligible, and precautionary measures should be proportionate. (On the facts, the mobile phone base station was allowed.)
• Statute. The Commonwealth Minister must take the precautionary principle into account in EPBC Act decisions (s 391).
• International. The principle has been cited in fisheries and ocean cases (the Southern Bluefin Tuna provisional measures, ITLOS, 1999) and underpins calls by dozens of states for a precautionary pause on deep-sea mining (see conflict over resources).

Why ESD is important

1. It integrates. ESD requires environmental, economic and social considerations to be weighed together, rather than treating protection as a barrier to development.
2. It guides decision-makers and courts. Because it is written into legislation, it gives courts (especially the NSW Land and Environment Court) a basis for reviewing decisions.
3. It shapes international law. The Rio principles appear in the UNFCCC, the CBD and the Paris Agreement, and the ICJ drew on them in 2025.
4. It gives criteria for evaluation. In an extended response, ask whether a response conserves biodiversity, treats future and present generations fairly and acts with precaution.

Evaluating ESD

Judgement. ESD is important and influential: it is the shared language of environmental law from the Rio Declaration to the EPBC Act, and courts have used it to protect endangered species and to require climate impacts to be assessed. Its effectiveness is limited because it is a set of principles to be balanced rather than rules that must be met, so economic considerations often prevail. The Environment Protection Reform Act 2025 (Cth), with its National Environmental Standards (framework in force from 2 December 2025; the first four standards made in August 2026), is an attempt to turn principles into enforceable standards; whether it succeeds is a live question for 2026 and 2027.

In one sentence

Ecologically sustainable development ties environmental law together by requiring decision-makers to conserve biodiversity, treat future generations and poorer people fairly and act with precaution, and it is written into international instruments, the EPBC Act and NSW law, but because it is weighed rather than enforced as a limit, it guides the law more effectively than it protects the environment.

Try this

Q1. Outline the precautionary principle. (3 marks)

• What the marker wants. Rio Principle 15 in your own words, with a legal source (EPBC Act s 391 or a case).

Q2. Explain the importance of biodiversity to ecologically sustainable development. (5 marks)

• What the marker wants. What biodiversity is, why it matters, the CBD and Kunming-Montreal framework, and an Australian law.

Q3. Assess the effectiveness of the law in achieving intergenerational equity. (8 marks)

• What the marker wants. Definition, examples (Oposa, Gray, Sharma, the ICJ opinion, Paris targets) and a judgement about why the law struggles to protect people not yet born.