‘This is a wonderful book that should be on the desk of every architect and planner. It shows how

Level 5 – Eco-cycling
Eco-cycling is introduced here to distinguish up-cycling that contributes to human and ecological 
health (ie net positive) from up-cycling that may still increase total resource flows or even encourage 
conspicuous consumption. That is, closing loops can be down-cycling, up-cycling or eco-cycling.
In addition to cleaning up a past problem, eco-cycling would also provide a public good
.
The Living 
Machine may best illustrate eco-cycling. Again, the Living Machine is a natural bioconversion process, 
where ecosystems of micro-organisms, usually in a sequence of transparent vats, treat sewage or 
wastewater, and grow food or fish. Living Machines can work at a neighbourhood, city or regional 
scale, while serving as landscape features and eco-tourist education facilities.
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They convert an 
unhealthy pollutant into healthy foods and products, such as the conversion of abattoir pollution to 
farm fertilizer, or turning urban food and plant waste into compost. They are arguably ‘reverse linear 
systems’ that turn negatives into positives.
Level 6 – Net positive
Innovations at this highest level improve whole systems health; that is, beyond the level of the product, 
building or city. Net positive would be eco-cycling that generates public goods as well as products 
with human and ecological health benefits. It applies to both physical or institutional design.
Net Positive Development
not only helps to transform its urban context (socially, economically and 
environmentally), but also:
•
Increases the ecological base (natural capital, eco-services, biodiversity, carrying capacity,
natural security, etc) through design for eco-services 
• 
Increases the public estate (access to life quality and the means of survival)
Eco-retrofitting can be net positive, as it can create positive public benefits beyond the original pre-
development site conditions and boundaries. (Note that rural systems can arguably be restored up 
to – but not beyond – original ecological conditions, so the term ‘eco-restoration’ is more appropriate 
in the rural context.)