Coral is a delicate organism on which an estimated million species depend. But as well as natural predators, coral is experiencing man-made troubles – its survival is now under threat from increasing average water temperatures, an effect of climate change. John Rumney runs an eco-tourism diving company on the Great Barrier Reef in northern Australia, the largest natural structure on earth. John has worked around the Reef for over 30 years, as a diver and a commercial fisherman. Now he worries that it could be facing extinction. John meets with Professor Ove Hoegh-Guldberg, one of the world’s leading experts on coral. He, too, is worried about the long-term damage caused by climate change. But his research suggests that assistance could come from a surprising source: the world of business.