Sustainability is an attempt to provide the best outcomes for the human and natural environments both now and into the indefinite future. It relates to the continuity of economic, social, institutional and environmental aspects of human society, as well as the non-human environment. It is intended to be a means of configuring civilization and human activity so that society, its members and its economies are able to meet their needs and express their greatest potential in the present, while preserving biodiversity and natural ecosystems, and planning and acting for the ability to maintain these ideals in a very long term. Sustainability affects every level of organization, from the local neighborhood to the entire planet.

Ways of looking at sustainability
Sustainability can be defined both qualitatively in words, and quantitatively as a ratio. Put in qualitative terms, sustainability seeks to provide the best outcomes for the human and natural environments both now and into the indefinite future.

The word sustainability (German: Nachhaltigkeit) was used for the first time in 1712 by the German forester and scientist Hans Carl von Carlowitz in his book Sylvicultura Oeconomica. French and English scientists adopted the concept of planting trees and used the term "sustained yield forestry".

The 1987 Brundtland Report, defined sustainable development as development that "meets the needs of the present generation without compromising the ability of future generations to meet their own needs". This is very much like the seventh generation philosophy of the Native American Iroquois Confederacy. Chiefs were charged with bearing in mind the effects of their actions on their descendants for seven generations.

The term "sustainable development" was adopted by the Agenda 21 program of the United Nations. The 1995 World Summit on Social Development further defined this term as "the framework for our efforts to achieve a higher quality of life for all people", in which "economic development, social development and environmental protection are interdependent and mutually reinforcing components"'. The 2002 World Summit on Sustainable Development expanded this definition identifying the "three overarching objectives of sustainable development" to be (1) eradicating poverty, (2) protecting natural resources, and (3) changing unsustainable production and consumption patterns.

Some people now consider the term "sustainable development" as too closely linked with continued material development, and prefer to use terms like "sustainability", "sustainable prosperity" and "sustainable genuine progress" as the umbrella terms. Despite differences, a number of common principles are embedded in most charters or action programmes to achieve sustainable development, sustainability or sustainable prosperity. These include (Hargroves & Smith 2005, see bibliography):

Dealing cautiously with risk, uncertainty and irreversibility.
Ensuring appropriate valuation, appreciation and restoration of nature.
Integration of environmental, social and economic goals in policies and activities.
Equal opportunity and community participation/Sustainable community.
Conservation of biodiversity and ecological integrity.
Ensuring inter-generational equity.
Recognizing the global dimension.
A commitment to best practice.
No net loss of human capital or natural capital.
The principle of continuous improvement.
The need for good governance.

Concepts and issues

Early influences
The modern concept of environmental sustainability goes back to the post-World War II period, when a utopian view of technology-driven economic growth gave way to a perception that the quality of the environment was linked closely to economic development. Interest grew sharply during the environmental movements of the 1960s, when popular books such as Silent Spring by Rachel Carson (1962) and The Population Bomb by Paul R. Ehrlich (1968) raised public awareness.

There are two related categories of thought on environmental sustainability. In 1968 the Club of Rome, a group of European economists and scientists, was formed. In 1972 they published Limits to Growth. Criticized by economists of the time, the report predicted dire consequences because humans were using up the Earth's resources and it advocated as one solution the abandonment of economic development. There followed the formation of groups sympathetic to the general premise that the human population on earth was growing too quickly and using up its resources. One such group was the Worldwatch Institute, founded in 1975. In a different category, other groups formed to focus less on population-growth control and slowing economic development and more on establishing environmental standards and enforcement. In retrospect, while some of the predictions made in Limits to Growth have proved to have been unfounded or premature, the warning it sounded is regarded as valid by many today.[1]

Ecosystems and use of resources
There is also a positive way to view sustainability: though values vary greatly in detail within and between cultures, at the heart of the concept of sustainability there is a fundamental, immutable value set that is best stated as 'parallel care and respect for the ecosystem and for the people within'. From this value set emerges the goal of sustainability: to achieve human and ecosystem well-being together. It follows that the 'result' against which the success of any project or design should be judged is the achievement of, or the contribution to, human and ecosystem well-being together. Seen in this way, the concept of sustainability is much more than environmental protection in another guise. It is a positive concept that has as much to do with achieving well-being for people and ecosystems as it has to do with reducing stress or impacts.

Many people have pointed to various practices and philosophies in the world today as being harmful to sustainability. For instance, critics of American society state that the philosophy of infinite economic growth and infinite growth in consumption are completely unsustainable and will cause great harm to human civilization in the future. In recognition that the Earth is finite, there has been a growing awareness that there must be limits to certain kinds of human activity if life on the planet is to survive indefinitely. In order to distinguish which activities are destructive and which are benign or beneficial, various models of resource use have been developed. Such models include: life cycle assessment and ecological footprint analysis. One of the striking conclusions to emerge from ecological footprint analyses is that it would be necessary to have 4 or 5 back up planets engage in nothing but agriculture for all those alive today to live as Westerns live. The algorithms of the ecological footprint model have, on the one hand, been used in combination with the emergy methodology (S. Zhao, Z. Li and W. Li 2005), and a sustainability index has been derived from the latter. They have also been combined with an index of quality of life (Marks et al, 2006),and the outcome christened the "(Un)Happy Planet Index" (HPI). Marks et al publish these indices for 178 nations, and some conclusions which will surprise many people emerge. For example, life expectancy and overall quality of life in the USA, although relatively high, are still not as high (in terms of international comparisons) as many people believe. But the other side of the coin is devastating. This quality is delivered at enormous cost (calculated in terms of its ecological footprint). A perhaps even more surprising finding is that a few nations, even in today's world, do manage to deliver long and high quality of life more or less within a sustainable economic footprint. The explanation of these surprises stems from the fact that, as Marks et al and, earlier, Lane (1991) had shown, quality of life stems primarily from things like security for the future and networks of social contact. It has little to do with the materialistic components generally used to calculate GNP. One way of summarising the outcome of this work is to view the American dream may as a Pied Piper unnecessarily leading us to our doom.

Population growth
One of the critically important issues in sustainability is that of human overpopulation combined with human lifestyle. A number of studies have suggested that the current population of the Earth, already over six billion, is too many people for our planet to support sustainably at current material consumption levels. This challenge for sustainability is distributed unevenly. According to calculations of the ecological footprint, the ecological pressure of a US resident is 13 times that of a resident of India and 52 times that of a Somalian resident.

Obviously, exponential growth is unsustainable in the long term, regardless of technology or lifestyle. For example, with the current population of 6.5 billion, at the current world growth rate of 1.4%/year, the population will reach 1.49x1014 in 722 years, which is equal to the number of square meters of land area on the earth. This is clearly an unfeasible situation. In fact, even if man were to travel into outer space at the speed of light, it still could not overcome exponential growth.

Critics of efforts to reduce population rather than consumption fear that efforts to reduce population growth may lead to human rights violations such as involuntary sterilization and the abandoning of infants to die. Some human-rights watchers report that this is already taking place in China, as a result of its one child per family policy.

Toward sustainability
The World Business Council for Sustainable Development, founded in 1995, has formulated the business case for sustainable development and argues that "sustainable development is good for business and business is good for sustainable development".

The international nonprofit The Natural Step, founded in 1989 by Swedish cancer scientist Karl-Henrik Robèrt, with the patronage of King Carl XVI Gustaf of Sweden, has coordinated a consensus process to define and operationalize sustainability. At the core of the process lies a consensus definition of sustainability, described as The System Conditions of sustainability.

Another application of sustainability has been in the Sustainable Livelihoods Approach, developed on conceptual work by Amartya Sen, and the UK's Institute for Development Studies (IDS). This was championed by the UK's Department for International Development (DFID), UNDP, Food and Agriculture Organization (FAO) as well as NGOs such as CARE, OXFAM and Khanya. Key concepts include the Sustainable Livelihoods (SL) Framework, a holistic way of understanding livelihoods, the SL principles, as well as 6 governance issues developed by Khanya. There is a website dedicated to the SL approach called Livelihoods Connect.

Types of sustainability
The Food and Agriculture Organisation (FAO) has identified considerations for technical cooperation that affect three types of sustainability:

Institutional sustainability. Can a strengthened institutional structure continue to deliver the results of technical cooperation to end users? The results may not be sustainable if, for example, the planning authority that depends on the technical cooperation loses access to top management, or is not provided with adequate resources after the technical cooperation ends. Institutional sustainability can also be linked to the concept of social sustainability, which asks how the interventions can be sustained by social structures and institutions;
Economic and financial sustainability. Can the results of technical cooperation continue to yield an economic benefit after the technical cooperation is withdrawn? For example, the benefits from the introduction of new crops may not be sustained if the constraints to marketing the crops are not resolved. Similarly, economic, as distinct from financial, sustainability may be at risk if the end users continue to depend on heavily subsidized activities and inputs.
Ecological sustainability. Are the benefits to be generated by the technical cooperation likely to lead to a deterioration in the physical environment, thus indirectly contributing to a fall in production, or well-being of the groups targeted and their society.
The United Nations has declared a Decade of Education for Sustainable Development starting in January of 2005. A non-partisan multi-sector response to the decade has formed within the U.S. via the U.S. Partnership for the Decade of Education for Sustainable Development. [2] Active sectors teams have formed for youth, higher education, business, religion, the arts, and more. Organizations and individuals can join in sharing resources and success stories, and creating a sustainable future.

Development sustainability
Sustainability is relevant to development projects. A definition of development sustainability is "the continuation of benefits after major assistance from the donor has been completed" (Australian Agency for International Development 2000). Ensuring that development projects are sustainable can reduce the likelihood of them collapsing after they have just finished; it also reduces the financial cost of development projects and the subsequent social problems, such as dependence of the stakeholders on external donors and their resources. All development assistance, apart from temporary emergency and humanitarian relief efforts, should be designed and implemented with the aim of achieving sustainable benefits. There are ten key factors that influence development sustainability.

Participation and ownership. Get the stakeholders (men and women) to genuinely participate in design and implementation. Build on their initiatives and demands. Get them to monitor the project and periodically evaluate it for results.
Capacity building and training. Training stakeholders to take over should begin from the start of any project and continue throughout. The right approach should both motivate and transfer skills to people.
Government policies. Development projects should be aligned with local government policies.
Financial. In some countries and sectors, financial sustainability is difficult in the medium term. Training in local fundraising is a possibility, as is identifying links with the private sector, charging for use, and encouraging policy reforms.
Management and organisation. Activities that integrate with or add to local structures may have better prospects for sustainability than those which establish new or parallel structures.
Social, gender and culture. The introduction of new ideas, technologies and skills requires an understanding of local decision-making systems, gender divisions and cultural preferences.
Technology. All outside equipment must be selected with careful consideration given to the local finance available for maintenance and replacement. Cultural acceptability and the local capacity to maintain equipment and buy spare parts are vital.
Environment. Poor rural communities that depend on natural resources should be involved in identifying and managing environmental risks. Urban communities should identify and manage waste disposal and pollution risks.
External political and economic factors. In a weak economy, projects should not be too complicated, ambitious or expensive.
Realistic duration. A short project may be inadequate for solving entrenched problems in a sustainable way, particularly when behavioural and institutional changes are intended. A long project, may on the other hand, promote dependence.

The Phenomenon of Change Resistance
The above concepts focus primarily on the proper practices required to live sustainably. However, there is also the need to consider why there is such strong resistance to adopting sustainable practices.

Unruh (2000, 2002) has argued that numerous barriers to sustainability arise because today's technological systems and governing institutions were designed and built for permanence and reliability, not change. In the case of fossil fuel-based systems this is termed "carbon lock-in" and inhibits many change efforts.

Thwink.org argues that if enough members of the environmental movement adopted a problem solving process that fit the problem, the movement would make the astonishing discovery that the crux of the problem is not what it thought it was. It is not the proper practices or technical side of the problem after all. Any number of these practices would be adequate. Instead the real issue is why is it so difficult to persuade social agents (such as people, corporations, and nations) to adopt the proper practices needed to live sustainably? Thus the heart of the matter is the change resistance or social side of the problem.

Sustainability metric and indices
In 2003, Maine [1] brought attention to the lack of quantitative indicators of sustainability. According to the University of Reading website[3], there are three basic functions of indicators: simplification, quantification, and communication. Indicators generally simplify in order to make complex phenomena quantifiable so that information can be communicated. In this context, in 1996 the International Institute for Sustainable Development developed a Sample Policy Framework which proposed that a sustainability index "would give decision- makers tools to rate policies and programs against each other" (1996, p.9). Like Maine, Ravi Jain (2005)[2] argued that, "The ability to analyze different alternatives or to assess progress towards sustainability will then depend on establishing measurable entities or metrics used for sustainability." Likewise the International Institute For Environment And Development, Environmental Planning Group (1993, p.2) said,

The need for sustainability analysis and particularly for indicators of sustainability is a key requirement to implement and monitor the development of national sustainable development plans, as required by Agenda 21 agreed at UNCED in June 1992.

A number of different schools have undertaken development of such a metric. In 1997 the Global Reporting Initiative (GRI) was started as a multi-stakeholder process and independent institution whose mission has been "to develop and disseminate globally applicable Sustainability Reporting Guidelines"[4]. The GRI uses ecological footprint analysis and became independent in 2002, and is an official collaborating centre of the United Nations Environment Programme (UNEP) and works in cooperation with UN Secretary-General Kofi Annan’s Global Compact. In the same year (1997), systems ecologists M.T.Brown and S.Ulgiati [3] [4] published their formulation of a quantitative sustainability index (SI) as a ratio of the emergy (spelled with an "m", i.e. "embodied energy", not simply "energy") yield ratio (EYR) to the environmental loading ratio (ELR). Brown and Ulgiati also called the sustainability index the "Emergy Sustainability Index" (ESI), "an index that accounts for yield, renewability, and environmental load. It is the incremental emergy yield compared to the environmental load" (1999, p. 7).

Sustainability definition as a ratio

NOTE: The numerator is called "emergy" and is spelled with an "m". It is an abbreviation of the term, "embodied energy", i.e. "embodied energy". The numerator is not "energy yield ratio" which is different. (This index is from Table 3. 'Global Energy Indices' in Brown and Ulgiati 1999, p.23)
More recently a joint initiative of the Yale Center for Environmental Law and Policy (YCELP) and the Center for International Earth Science Information Network (CIESIN) of Columbia University, in collaboration with the World Economic Forum and the Joint Research Centre of the European Commission also attempted to construct an Environmental Sustainability Index (ESI). This was formally released in Davos, Switzerland, at the annual meeting of the World Economic Forum (WEF) on 28 January 2005. The report on this index made a comparison [5] of the WEF ESI to other sustainability indicators such as the Ecological footprint Index. However there was no mention of the emergy sustainability index. Nevertheless writers like Leone[5] and Yi et al. [6] have also recently suggested that the emergy sustainability index has significant utility. In particular, Leone notes that while the GRI measures behavior, it fails to calculate supply constraints which the emergy methodology aims to calculate.

See also a recent report by United States Environment Protection Agency using emergy methodology [6], and compare also with the Dow Jones Sustainability Index.

See also a recent (June, 2006) peer-reviewed study [7], The 2006 US City Rankings, by SustainLane.com[8], ranking the 50 most populated U.S. cities across 15 categories, utilizing over 2000 data points.

[edit] Sustainability and competitiveness
According to some economists, it is possible for the concepts of sustainable development and competitiveness to merge if enacted wisely, so that there is not an inevitable trade-off. This merger is being motivated by the following six facts (Hargroves & Smith 2005):

Throughout the economy there are widespread untapped potential resource productivity improvements to be made to be coupled with effective design.
There has been a significant shift in understanding over the last three decades of what creates lasting competitiveness of the firm.
There is now a critical mass of enabling technologies in eco-innovations that make integrated approaches to sustainable development economically viable.
Since many of the costs of what economists call ‘environmental externalities’ are passed on to governments, in the long-term sustainable development strategies can provide multiple benefits to the tax payer.
There is a growing understanding of the multiple benefits of valuing social and natural capital, for both moral and economic reasons, and including them in measures of national well-being.
There is mounting evidence to show that a transition to a sustainable economy, if done wisely, may not harm economic growth significantly, in fact it could even help it. Recent research by ex-Wuppertal Institute member Joachim Spangenberg, working with neo-classical economists, shows that the transition, if focused on improving resource productivity, will lead to higher economic growth than business as usual, while at the same time reducing pressures on the environment and enhancing employment.

[edit] Barriers to Ecological Sustainability
Despite the now overwhelming evidence (only some of which has been reviewed above) that our species is set on a disaster course of immense proportions, and despite long-standing and widespread public awareness of the seriousness of the problem (eg Nelson, 1986; Yankelovitch, et. al., 1983), it seems impossible to alter the course of our destiny.

This is generally attributed to “change resistance” (see, eg Thwink.org, viewed as involving change in individual values, whether at personal, corporate, or collective levels (see eg Stafford Beer). Unfortunately, it has been frequently demonstrated, eg in the studies cited in the last paragraph, that people’s values are, in general, in the right place. The problem is to enact them. This has led to the preparation of numerous “wish lists” – such as that compiled by Shah, H., & Marks, N. (2004) – drawing together many recommendations for government action.

Government and individual failure to act on the available information is widely attributed to personal greed (deemed to be inherent in human nature) especially on the part of international capitalists. But even Karl Marx did not suggest this, instead highlighting sociological processes which have been in operation for thousands of years. If fault is to be found with Marx's work it can be argued that it lies elsewhere. Because he believed that the collapse of capitalism was imminent, he never discussed how to run society in an innovative way in the long term public interest.

Two things seem to follow from this brief discussion. (1) it is vital to follow up Marx’s scientific study of the socioybernetic (see sociocybernetics), or systems (see also systems theory), processes which, it seems, primarily control what happens in society. (2) To use the social-science-based insights already available to evolve forms of Public management that will act on information in an innovative way in the long term public interest. (The limitations of current forms of Public management and possible ways forward are discussed in a specially prepared Wikipedia article on that topic.)

Notes
? M. Leone (2005). "The Quest for an Environmental Metric: Gazing at weather systems, a ground-breaking scientist spawned an ecological accounting standard that Wall Street might one day embrace". CFO Publishing.
? T. Maine (2003). "Towards a Metric of Sustainability". CSIRO Publishing.
? M.T. Brown and S. Ulgiati (1997). "Emergy-based indices and ratios to evaluate sustainability: monitoring economies and technology toward environmentally sound innovation". Ecological Engineering 9: 51-69.
? M.T. Brown and S. Ulgiati (1999). "Emergy Evaluation of the Biosphere and Natural Capital". Ambio 28 (6).
? S. Zhao, Z. Li, W. Li (2005). "A modified method of ecological footprint calculation and its application". Ecological Modelling 185 (1): 65-75. DOI:10.1016/j.ecolmodel.2004.11.016.
? Heui-seok Yi, Jorge L. Hau, Nandan U. Ukidwe, and Bhavik R. Bakshi (2004). "Hierarchical Thermodynamic Metrics for Evaluating the Environmental Sustainability of Industrial Processes". Environmental Progress 23 (4): 65-75. DOI:10.1002/ep.10049.
? R. Jain (2005). "Sustainability: metrics, specific indicators and preference index". Clean Techn Environ Policy 7: 71-72.

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