There are few bigger issues than climate change. But back in 2008, the public discussion was still trapped in the debate between climate scientists and climate change sceptics.

Most of the government’s marketing and communications until that point had been focused on trying to win the argument, and persuade the sceptics.

This wasn’t working - in fact, by giving oxygen to the debate, it made individuals feel powerless. David’s answer was to speak directly to the majority who were already persuaded, to treat the debate as won and to help people take action now to limit their carbon footprint.

And so, the Act on CO2 campaign was born, using behavioural science approaches to help people find the right, manageable actions they could take to play their part in the fight against climate change.