WED, as it is often called, was established by the United Nations General Assembly to mark the start of the UN Conference on the Human Environment held in Stockholm from 5thto 16th June 1972. The first World Environment Day was on 5th June 1973.

The Stockholm Conference was the first occasion that world leaders met to discuss the political, social and economic problems of the global environment with a view to actually doing something about it.
Each year World Environment Day is hosted by a different country and this year the host is Brazil and the theme is Green Economy: Does it include you?

A Green Economy, according to the United Nations Environment Programme, is one that results in improved human well-being and social equity, while significantly reducing environmental risk and ecological scarcities.