A green economy is one that results in improved human well-being and social equity, while significantly reducing environmental risks and ecological scarcities. In its simplest expression, a green economy is low-carbon, resource efficient, and socially inclusive (UNEP 2011).

The definition of a green economy makes explicit reference to resource efficiency as one of its key pillars.

A planetary boundaries framework defines a safe operating space for humanity to develop and thrive, according to nine defined biophysical processes that regulate the earth’s system (Rockström et al., 2009). It provides a science-based analysis of the risks caused by human activities interfering with the earth’s natural functions (although is less directly relevant at the scale of cities (Steffen et al., 2015).

Relevant for considering integrated approaches that recognise trans-boundary use and protection of natural resources.

This framework can also inform the definition of resource efficiency targets at city-level.

The environmental footprint is a means of measuring the impacts of a person, company, activity, product, etc. on the environment. An ultimate aim of this measurement is to reduce the environmental footprint of actors by conserving, restoring, and replacing the natural resources they use (Jensen, 2013). The framework has been applied specifically to cities (Wackernagel et al. 2006).

A focus on environmental footprints can be an important driver for resource efficiency.

The maximum amount of carbon that can be emitted to the atmosphere in order to avoid dangerous climate change with a translation in terms of a maximum of fossil fuels we can extract from the ground (IPCC, 2013).

Developing policies that will enable to manage carbon budgets require management of resources in a way that minimises emissions and waste production.

Relative decoupling refers to a lower rate in growth of a type of environmental pressure in relation to the rate of growth of a related economic activity. Absolute decoupling refers to an environmental pressure either remaining stable or decreasing while the related economic activity increases (Watson et al., 2014).

Decoupling can contribute directly to resource efficiency. Cleaner production practices and technologies provide opportunities for small business development and the creation of green jobs (UNEP, 2010; Swilling et al., 2013).

Current patterns of production and consumption lead to a wasteful use of resources – but also to inequality and poverty (Rode and Burnett, 2011; UNEP, 2011).

Resource efficiency can lead to investment in the creation of jobs and the enhancement of human well-being.