Communications giant BT had made huge progress, reducing the carbon intensity of its operations by 57% in March 2010, from 1997 levels.
But it wanted to go further and knew it could not achieve a more ambitious 80% reduction target by 2020 unless it had the wholehearted support of thousands of companies in its supply chain.
Spending nearly £12bn a year on goods and services, BT is supplied by businesses all over the world, many in developing companies.
These suppliers are expected to meet BT's own standards on human rights, working conditions and environmental protection. All contracts are underpinned by BT's "sourcing with human dignity" code and by the climate change procurement standard, one of the first of its kind in the UK.
In 2007, BT told suppliers it planned to raise the bar on environmental protection and energy efficiency and environment would be treated as key factors in 80% of its purchasing decisions. In addition 80% of products being replaced would need to be more environmentally-friendly.
The move produced results. By March 2010, 50% of suppliers were measuring their carbon footprint and 52% had set their own reduction targets.
Encouraged by these early results, the group looked for ways to get more suppliers involved. Working with the Carbon Trust it developed a supplier engagement programme, running a series of one-day workshops to share knowledge and to help suppliers understand the benefits of using energy more efficiently and cutting CO2.
Attendees were asked at the end of each session to set outline action plans for their own business, including how they would communicate with stakeholders and implement change, and commit to a firm plan within two weeks. BT checked on progress within six to eight weeks.
By the end of 2010, 80 suppliers had attended the workshops and, despite some initial scepticism, the programme is now achieving very high scores in terms of relevance and interest.
Simon Beavis is part of the wordworks network
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