World leaders need to recognise the importance of the environment in tackling the problems facing the global economy, campaigners have urged.
And they need to send a clear signal to businesses to give them the confidence to invest in green technology such as offshore wind and vehicles with low emissions in order to boost struggling economies.
The call comes as ministers from around the world gather for a key environmental summit in Rio de Janeiro, Brazil, where the "green economy" will be one of the main areas for discussion.
It is also hoped ministers will agree on a plan to draw up new "sustainable development goals" to tackle issues such as providing food, water and clean energy for people around the world.
But negotiations in the run up to the conference, which marks 20 years since the original Earth Summit that set the environmental agenda for two decades, have stuttered.
And with European countries gripped by the Eurozone crisis and many world leaders staying away from the conference, there are concerns about how much can be achieved.
Friends of the Earth's director of policy and campaigns Craig Bennett said the ongoing financial crisis provided an opportunity for leaders to recognise that the mess economies were in was due to a lack of regulation and that the system should not just be put back as it was.
He called for the conference to define a "good" green economy that was sustainable and worked for local communities, not just providing cover for business as usual, and for progress to be made on providing genuinely clean energy for all.
And he said: "If governments were to give long, loud and legal messages about what kind of investments are going to do well in the future, business will invest. The money is there, the confidence is not there."
Environmentalists see developing clean technology and services as a way of setting the world on a more sustainable path while tackling the recession.