Policy Implications of Scale Dynamics   Many policy implications flow from these dynamics:

• Its is more desirable for economically driven levels of throughput to be sustainable than unsustainable (as sustainable levels maintain ecosystem functions that economic and other vital life support activities depend on)
• If levels of economically driven throughput are unsustainable, efforts should be made to reduce throughput levels, and return to sustainable levels as soon as possible (as the longer we operate at unsustainable levels the more we degrade ecosystems and their ability to regenerate, and the more difficult and costly will be the process of restoring sustainable scale)
• Maximum scale is to be avoided.  Exceeding maximum scale represents an irrevocable loss of critical ecosystem functions that threaten human well being and survival.
• Optimal scale is the policy priority. If a sustainable level of throughput is close to maximum sustainable scale there is always the possibility that some unforeseen natural or anthropogenic events could push the level of throughput to an unsustainable level.  It is desirable to manage our level of economic throughput so that such an inadvertent transition to unsustainable scale does not occur.  This involves assessing risks, as well as other ethical issues, for current and future generations of humans and other species. Also to be considered is the level of material goods and services desirable for human well being.  Broad participation is needed to determine the socio-political priorities of optimal scale.

Optimal Scale: the Policy Priority    The concept of optimal scale incorporates ecological sustainability as well as social and ethical concerns.  It identifies the level of economically driven material throughput that is most desirable from these multiple perspectives, each so fundamental to human well being – the level of throughput which provides the greatest economic, environmental and social benefits.  One of the social and ethical considerations involves the responsibilities of the present generation to future generations of humans and other species. One aspect of such considerations is the safety margin that is acceptable in terms of inadvertently exceeding sustainable scale, and thereby slipping into unsustainable practices. 

Creating a Safety Margin: Accepting Limits    Unsustainable levels of throughput are dangerous because of the degradations they impose on critical life support systems; they are to be avoided.  But the biophysical limits which determine ecological sustainability are complex, dynamic, and non-linear, making it difficult to describe the boundary between sustainable and unsustainable throughput with great precision. This means limiting the level of material throughput below the level that is maximally sustainable, to create a safety margin.  But the less material throughput we have, the fewer material goods and services we have to enjoy.  The current economic paradigm assumes that more material goods and services mean greater human happiness and well being.  Optimal scale recognizes that material goods are only one of the determinants of human happiness and well being (see Real Determinants of Human Happiness and Well Being).

Managing Global Material Throughput   The concept of sustainable scale provides a conceptual framework for managing the level of economically driven material throughput so that it remains within the safe, sustainable range. This framework assists us to get the most benefits from economic activities, as well as from the non-market benefits of life support ecosystems.  As a relational concept (throughput relative to optimal regeneration) it requires a new way of thinking about how to integrate economic, ecological and social/justice priorities and activities.  What we have learned to do effectively (if not necessarily efficiently) in the last 150 years is how to drive throughput in economic activities.  We have yet to learn how to mange throughput levels to remain within the biophysical limits of ecosystems, and the ethical limits of our highest common aspirations.