The twelve leverage points to intervene in a system were proposed by Donella Meadows. Donella Dana Meadows (March 13, 1941 Elgin, Illinois, USA - February 20, 2001, New Hampshire) was a pioneering environmental scientist, a teacher and writer. ...

Meadows worked in the field of systems analysis and proposed a scale of places to intervene in a system. To the degree that the observer is within the system, or "part of it", awareness and manipulation of these levers is an aspect of self-organization. Systems analysis is the science dealing with analysis of complex, large scale systems and the interactions within those systems. ... For the Macintosh operating system, which was called System up to version 7. ... Self-organization refers to a process in which the internal organization of a system, normally an open system, increases automatically without being guided or managed by an outside source. ...

When done collaboratively, it can lead to collective intelligence. Her observations are often cited in energy economics, green economics and human development theory. Collective intelligence as characterized by Tom Atlee, Douglas Engelbart, Cliff Joslyn, Ron Dembo, and other theorists, is that which overcomes groupthink and individual cognitive bias in order to allow a relatively large number of people to cooperate in one process - leading to reliable action. ... Energy economics is a subfield of economics that focuses on energy relationships as the foundation of all other relationships. ... Green economics loosely defines a theory of economics by which an economy is considered to be component of the ecosystem in which it resides. ... Human development theory is an economic theory that merges older ideas from ecological economics, sustainable development, welfare economics, and feminist economics. ...

She started with the observation that there are levers, or places within a complex system (such as a firm, a city, an economy, a living being, an ecosystem, an ecoregion) where a "small shift in one thing can produce big changes in everything" (compare: constraint in the sense of theory of constraints). A complex system is a system whose properties are not fully explained by an understanding of its component parts. ... In ecology, an ecosystem is a community of organisms (plant, animal and other living organisms - also referred as biocenose) together with their environment (or biotope), functioning as a unit. ... An ecoregion is a relatively large area of land or water that contains a geographically distinct assemblage of natural communities. ... A constraint is a limitation of possibilities. ... Theory of constraints (TOC) is a body of knowledge on the effective management of (mainly business) organizations, as systems. ...

She claimed we not only need to realize the existence of these shifts (or leverage points) but also to know where they are and how to use them. According to her, most people know where these points are instinctively, but tend to adjust them in the wrong direction. The understanding of these leverage points would be powerful information to solve major global problems such as unemployment, hunger, economic stagnation, pollution, resources depletion, and conservation issues. Unemployment rates in the United States. ... Hunger is applied literally to the need or craving for food; it can also be applied metaphorically to cravings of other sorts. ... Pollution is the release of harmful environmental contaminants, or the substances so released. ... Resource depletion is an economic term referring to the exhaustion of raw materials within a region. ... Conservation may refer to the following: Conservation ethic in relation to preserving ecosystems Conservationist Conservation movement Conservation law of physics Conservation of energy Conservation of mass Conservation in genetics This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ...

After Donella Meadows developed an initial nine points list of places to intervene during a meeting, she detailed a twelve leverage points list with further explanation and examples, for systems in general.

She describes a system as being in a certain state, and containing a stock, with inflows (amounts coming into the system) and outflows (amounts going out of the system). At a given time, the system is in a certain perceived state. There may also be a goal for the system to be in a certain state. The difference between the current state and the goal is the discrepancy. For the Macintosh operating system, which was called System up to version 7. ... See stock (disambiguation) for other meanings of the term stock A stock, also referred to as a share, is commonly a share of ownership in a corporation. ... There is more than one usage of the word goal. ...

For example, one might consider a lake or reservoir, which contains a certain amount of water. The inflows are the amount of water coming from rivers, rainfall, drainage from nearby soils, and waste water from a local industrial plant. The outflows might be the amount of water used up for irrigation of nearby cornfield, water taken by that local plant to operate as well as the local camping site, water evaporating in the atmosphere, and trickling surplus water when the reservoir is full.

Local inhabitants complain about the water level getting low, pollution getting higher, and the potential effect of hot water release in the lake on life (in particular, the fish).

This is the difference between the perceived state (pollution or low water level) and the goal (a non-polluted lake).

Twelve leverage points to intervene in a system (in increasing order of effectiveness)

12. Constants, parameters, numbers (such as subsidies, taxes, standards)

Parameters are points of lowest leverage effects. Though they are the most clearly perceived among all leverages, they have little effect long term; they do not usually change behaviors. A widely changing system will not be made stable by a change of parameter, nor will a stagnant one dramatically change.

For example, climate parameters may not be changed easily (the amount of rain, the evapotranspiration rate, the temperature of the water), but they are the ones people think of first (they remember that in their youth, it was certainly raining more). These parameters are indeed very important. But even if changed (improvement of upper river stream to canalize incoming water), they will not change behavior much (the debit will probably not dramatically increase).

11. The size of buffers and other stabilizing stocks, relative to their flows

A buffer is a stabilizing stock. The stabilizing buffer is important when the stock amount is much higher than the potential amount of inflows or outflows. In the lake, the volume of water in the lake is the buffer: if there's a lot more of it than inflow/outflow, the system stays stable. Buffer can have various meanings: In chemistry, the term buffer refers to a buffer solution, usually used to stabilize the acidity (pH) of a liquid. ...

For example, the inhabitants are worried the lake fish might die as a consequence of hot water release directly in the lake without any previous cooling off.

However, the water in the lake has a large heat capacity, so it's a strong thermic buffer. Provided the release is done at low enough depth, under the thermocline, and the lake volume is big enough, the buffering capacity of the water might prevent any extinction from excess temperature.

Buffers may have great effect to improve a system, but they are often physical entities, where size is critical and can't be changed easily (for example, the lake capacity is restricted). Heat capacity (abbreviated Cth or just C, also called thermal capacity) is the ability of matter to store heat. ... The thermocline is a layer within a body of water where the temperature changes rapidly with depth. ...

10. The structure of material stocks and flows (such as transport network, population age structures)

The structure of the system may have enormous effect on how the system operates. So it might also be a leverage point to act on. However, if a system structure was not built properly, the cost, delays and externalities of the rebuilding may be prohibitive. Sometimes, the structure cannot even be changed at all. So the leverage point might be to understand the system limitations and bottlenecks, and to work on fluctuations.

For example, the inhabitants are worried about their lake getting polluted, as the industry releases chemicals pollutants directly in the water without any previous treatment. The system might need the used water to be diverted to a waste water treatment plant, but this requires rebuilding the underground used water system (which could be quite expensive).

9. The length of delays, relative to the rate of system changes

Another leverage point is in the length of delays. Delays must be carefully considered, as information received too quickly or information received too late could cause either overreaction and underreaction. Very lengthy delays cause oscillations when trying to adjust a system. However, delays are often parameters that can be changed as easily as rate of change. Delay is: In sound effects, any of a class of effect that adds one or more delayed versions of the original signal, to create effects such as echo or flanger. ...

For example, the city council is considering building the waste water treatment plant. However, the plant will take 5 years to be built, and will last about 30 years. The first delay will prevent the water being cleaned up within the first 5 years, while the second delay will make it impossible to build a plant with exactly the right capacity.

8. The strength of negative feedback loops, relative to the effect they are trying to correct against

A negative feedback loop is a control that tend to slow down a process (it refers to the direction of the change). In a system going forward, the negative loop will tend to promote stability (stagnation). The loop will keep the stock near the goal, thanks to parameters, accuracy and speed of information feedback, and size of correcting flows. Negative feedback is a type of feedback, during which a system responds so as to reverse the direction of change. ...

For example, one way to avoid the lake getting more and more polluted might be through setting up an additional tax, relative to the amount and the degree of the water released by the industrial plant. The tax might lead the industry to reduce its releases.

7. The gain around driving positive feedback loops

A positive feedback loop is a control that tends to speed up a process (it refers to the direction of the change). It is a self-reinforcing loop. Positive feedback loop are sources of growth, of explosion, and sometimes of collapse when the feedback is not under control (in particular of a negative feedback loop). Dana indicates that in most cases, it is preferable to slow down a positive loop, rather than speeding up a negative one. Positive feedback is a type of feedback. ...

The eutrophication of a lake is a typical feedback loop that goes wild. In an eutrophic lake (which means well-nourished), lots of life can be supported (fish included).

An increase of nutrients will lead to an increase of productivity, growth of phytoplankton first, using up as much nutrients as possible, followed by growth of zooplankton, feeding up on the first ones, and increase of fish populations. The more nutrients available there is, the more productivity is increased. As plankton organisms die, they fall at the bottom of the lake, where their matter is degraded by decomposers.

However, this degradation uses up available oxygen, and in the presence of huge amounts of organic matter to degrade, the medium progressively becomes anoxic (there is no more oxygen available). Upon time, all oxygen-dependent life dies, and the lake becomes a smelly anoxic place where no life can be supported (in particular no fish).

6. The structure of information flow (who does and does not have access to what kinds of information)

Information flow is a very important leverage point in a system. It is neither a parameter, nor a re-inforcing or slowing loop, but a new loop delivering information that was not delivered before. It is considered a very powerful leverage, cheaper and easier than infrastructure change. Information is a term with many meanings depending on context, but is as a rule closely related to such concepts as meaning, knowledge, instruction, communication, representation, and mental stimulus. ...

For example, a monthly public report of water pollution level, especially nearby the industrial release, could have a lot of effect on people's opinions regarding the industry, and lead to changes in the waste water level of pollution.

5. The rules of the system (such as incentives, punishment, constraints)

Rules are very high leverage points. Dana Meadows points out the importance of paying attention to rules, and mostly to who make them.

For example, a strengthening of the law related to chemicals release limits, or an increase of the tax amount for any water containing by a given pollutant, will have a very strong effect on the lake water quality.

4. The power to add, change, evolve, or self-organize system structure

Self-organization refers to the capacity of a system to change itself by creating new structures; adding new negative and positive feedback loops, promoting new information flows, making new rules. Self-organization refers to a process in which the internal organization of a system, normally an open system, increases automatically without being guided or managed by an outside source. ...

For example, microorganisms have the ability to not only change to fit their new polluted environment, but also to undergo an evolution that make them able to biodegrade or bioaccumulate chemical pollutants. This capacity of part of the system to participate to its own eco-evolution is a major leverage for change

The term eco-evolution was coined by Donella Meadows to describe the power to add, change, evolve, or self-organize system structure which she described as the fourth most powerful way to intervene in a system: Self-organization refers to the capacity of a system to change itself by creating...

3. The goal of the system

A goal change has effect on every item listed above, parameters, feedback loops, information and self-organisation.

A city council decision might be to change the goal of the lake from making it a free facility for public and private global use, to a more touristic oriented facility or a conservation area. That goal change will effect several of the above leverages : information on water quality will become mandatory and legal punishments will be set for any illegal polluted effluent.

Ecotourism essentially means ecological tourism, where ecological has both environmental and social connotations. ... Conservation may refer to the following: Conservation ethic in relation to preserving ecosystems Conservationist Conservation movement Conservation law of physics Conservation of energy Conservation of mass Conservation in genetics This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ...

2. The mindset or paradigm that the system — its goals, structure, rules, delays, parameters — arises out of

A society paradigm is an idea, an unstated assumption (because it is unnecessary to state it) that everyone shares, thoughts, or states of thoughts that are sources of systems. Any set of assumptions becomes a paradigm, and therefore re-examining all the fundamental assumptions may lead to new paradigms. Paradigms are very hard to change, but there are no limits to paradigm change. It just requires another way of seeing things. Dana indicates paradigms might be changed by repeatedly and consistently pointing out anomalities and failures to those with open minds. A mindset, in decision theory and general systems theory, refers to a set of assumptions, methods or notations held by one or more people or groups of people which is so established that it creates a powerful incentive within these people or groups to continue to adopt or accept prior... From the late 1800s the word paradigm refers to a thought pattern in any scientific discipline or other epistemological context. ...

A current paradigm is "Nature is a stock of resources to be converted to human purpose". What might happen to the lake were this collective idea changed ?

1. The power to transcend paradigms

Transcending paradigms may go beyond challenging fundamental assumptions, into the realm of changing the values and priorities that lead to the assumptions, and being able to choose among value sets at will. The power of this ability may be literally godlike.

Many today see Nature as a stock of resources to be converted to human purpose. Many Native Americans see Nature as a living god, to be loved, worshipped, and lived with. These views are incompatible, but perhaps another viewpoint could incorporate them both, along with others.

See also

• focused improvement
• constraint, theory of constraints,
• Complexity, Problem Solving, and Sustainable Societies — Joseph Tainter
• Systemantics — John Gall