To me there seemed to be two worlds operating in parallel at Rio; the political world - based around the formal conference and the outcome document - ground to a halt in a sea of nothingness.

But the business community was full of energy and enthusiasm and broke away from the formal process in a way that was liberating and forward-looking.

For a long time, the business community has said that governments must provide clarity, a long-term perspective and a sense of direction. They have lobbied for a formal seat at the table at these types of negotiations. They have waited for governments to respond to these demands and the response has not come.

Policymakers are paralyzed by the state of their economies and domestic political events, and hampered by a lack of clear signals from voters that would give them a mandate to move forward with vision and courage.

What was positive at this summit was that businesses did not sit back and wait. Many have recognized that sustainability megaforces such as climate change, water scarcity, food security and urbanization are not waiting for the politicians to make up their minds. Instead, businesses have taken action on their own.

Another important shift I noticed was the emphasis on opportunity rather than risk. Leading businesses have recognized that the world is changing and that if they are to be fit for the future, they need to change with it. For them, that debate is over. What is different now is a new focus on how they can address the triple bottom line of people and planet along with profit. There has been a shift from problem thinking to solution thinking.

Of course, I am not saying that every business has made this shift. Not every business has yet recognized the risks of sustainability megaforces let alone the opportunities. There are plenty of companies around the world that still view "going green" with suspicion or as an optional philanthropic bolt-on rather than good business sense.

But the word "leader" would be meaningless if there were no followers and no laggards. The point here is that the critical mass of sustainability leaders is growing. Visionaries like Paul Polman of Unilever and Jochen Zeitz of PPR are no longer lone voices in the wilderness. "Sustainability" is no longer the dirty word it once was in the mainstream. Rio+20 was full of signs that a new breed of business leader is emerging, unafraid to challenge conventions and drive change.

I have been asked what lessons businesses should take-away from the summit. In response, I say three things:

Firstly, do not make the mistake of thinking that the green economy has disappeared because of the weak political outcome of Rio+20. It has not. It is developing from the bottom up rather than being imposed from the top down. Ignore it at your peril.

Secondly, be aware. The fragmented nature of piecemeal action makes progress complex to follow, but it is in your interest to stay connected. Things may move more quickly than you expect.

And finally, be bold in thinking about opportunity, not just risk. There is early mover advantage for companies that refuse to be constrained by the lack of policy framework. They are taking action because they see it as being in the best interest of their businesses.

Yvo de Boer is the Special Global Advisor, KPMG Climate Change & Sustainability

www.kpmg.com