As environmental crises and the urgency to create ecological sustainability escalate, so does the importance of ecological economics. This applied, solutions-based field of studies is concerned with sustainability and development, rather than efficiency and growth. Also, given that cities account for 70-80% of global economic activity and associated resource use, emissions and waste, they are central to finding solutions to the challenge of sustainability. Ecological economics recognises local to global environmental limits. It ranges from research for short-term policy and local challenges through to long-term visions of sustainable societies. Ecological economists also consider global issues such as carbon emissions, deforestation, overfishing and species extinctions. To view the full article visit the Conversation.com.