As the SMI-Wizness Social Media Sustainability Index documents, big bold campaigns still played an important role in 2012 – Sony's Futurescapes, Siemens' Answers and Microsoft's Youthspark stood out. However, an increasing number of companies, including GE, Renault, Ford and this year's index leader, Levi Strauss, put stock in developing a strong editorial voice. We call it a "magazine mentality", enabling an always on and always accessible channel of sustainability communication with investors, employees, media, NGOs and, yes, customers.

This magazine mentality was triggered by a simple yet complicated reality: sustainability is no longer only of interest to niche stakeholders. For companies, that poses an intriguing opportunity of communicating sustainability to a large audience and a thorny problem of how to do that in an engaging, compelling manner. A smart editorial approach isn't the only best practice theme highlighted in the research. Companies on the index are also embracing games, apps and maps along with new and emerging social media platforms as well as reimagining the way their sustainability reports can be packaged and shared.

Social media has been the driving force behind this change of audience and community. By empowering people with the sensibility that their voice matters and can make a difference, social media technologies have changed forever the way people communicate and act online. Sustainability practitioners at first were slow to realise social media's potential to help communicate their efforts but over the last three years they've made up for lost time.

Indeed, in 2010, when we first published this index, just 60 companies had dedicated social media channels to talk about sustainability. By 2011 that number had doubled. For 2012, we found 176 major companies around the world that had allotted dedicated resources and social media channels to their sustainability dialogue.

It was no surprise to see that Twitter and Facebook were favourite channels for sustainability communicators. Of more interest were the 60 dedicated blogs or sustainability social media magazines being published, suggesting the continued importance of editorial storytelling in describing a company's practice on sustainability and corporate social responsibility.

How has social media driven this change in how sustainability is communicated? For one thing, the connected, amplified voice of social media has made it very difficult for companies to ignore their own responsibilities to the environment and their communities – a viral-bully pulpit that NGOs such as Greenpeace have become experts in mobilising.

But put aside the need to defend brand reputation and a more forward-looking picture emerges of why social media and sustainability work well together. We believe that the foundations of both social media and sustainability are authenticity, transparency, community, innovation and creativity. The five leading companies in this year's index, Levi Strauss, BBVA, eBay, Danone, and GE all demonstrate those attributes.

Social is no longer a new and trendy form of online media. It has become the mainstream and is embedded in every form of online communication but also in the sensibilities and expectations of everyone online. So how companies understand and use social media to communicate their sustainability activities will only grow in importance as it too becomes part of the business communication mainstream. You can read how the leading 100 companies are progressing on that journey in this year's index, available online at the Wizness site or as a download from SMI.

Matthew Yeomans is the co-founder of Social Media Influence and director of Custom Communication, a social media sustainability consultancy and he tweets @mateoy.

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