So how can consumers be persuaded to act? The first option is to explore generic insight into behaviour change. Unilever, for example, has defined five levers for sustainable living or tips to persuade consumers to act. Make it: understood; easy to act; desirable; rewarding; and habitual.

The board is eyeing up other industries - with pilots underway in clean water technology, new concepts for retail, and sustainable homes. And it's also probing new markets, beginning with the US...

It's all a far cry from what could be described as the comparatively sober, 'traditional' Indian corporate approach to sustainability, rooted in a long tradition of philanthropy. It's a tradition which has been absorbed smoothly into the relatively recent concept of corporate social responsibility (CSR).

I believe that the 'flywheel' of business change is starting to spin faster. Why? Because the drivers for change are becoming starker and because the necessary business response is better understood.

It's been a mixed year for sustainable business. For every signal telling us to become more sustainable (resource crunch, extreme weather, social disquiet with business) a counter signal (austerity, shale gas discovery, political inertia) suggests that business as usual is the safest thing to do.

"Do not be mistaken. There are many thousands of business leaders and investors at all scales who want to align their actions and their decisions with...

It is in the area of corporate sustainability that we believe crowdsourcing has the greatest latent potential. This is because the nature, scale and complexity of the challenges demand businesses not only to think outside of the box but to reimagine the box itself.

When we launched our eco and ethical programme, Plan A, in 2007 we made some big bold product related commitments. For example, to get all our wood and fish from the most sustainable source possible. It wasn't the wrong thing to do but we were looking through the lens of 'issue' rather than 'product'.

In many ways, the Rio+20 Earth Summit is a huge distraction; with an estimated 50,000 participants, and so much time, money and energy spent on negotiations for something that, in reality, is non-negotiable.

In the fifth and final part of our 'Sustainable Business: As If people Matter' series, Michael Townsend looks at the skills challenge - and how we might close the gap as we move towards a sustainable and low-carbon economy.

Who would want to be a business leader in these volatile times? The debate about boardroom pay and excess rages, the global economy is so volatile it is hard to plan anything with conviction, issues of ethics and trust echo through the media, and then there are more icebergs looming on the horizon: resource scarcity, soaring energy prices, and the increasing impact of climate change.

To ensure that we have enough customers, we need to make sure enough people have jobs, and with that sufficient disposable income with which to meet their 'needs' and, if they are lucky, stretch to a few 'wants' as well.

Ultimately, the transition towards sustainable business is inevitable, given the combined impact of the challenges we face. For those businesses looking to fully embed sustainability principles, there is also a big prize waiting. And who wouldn't want some of that?

Sportswear and fashion company Puma has revealed the full extent of its ecological footprint, after going through a groundbreaking exercise to quantif...