Alongside global warming, the destruction of the world’s biodiversity and natural capital threatens to undermine economic growth. Another 3 billion people and a world economy some 16 times bigger by 2100 threatens environmental destruction on a scale which would make the twentieth century look positively benign. On current policies, natural capital – those assets nature gives us for free – will be massively depleted and undermine economies. To put growth on a sustainable basis requires that natural assets are taken seriously – in national and corporate accounts, on balance sheets, and by providing compensation for damage, pollution taxes and a nature fund. This lecture sets out how to do this, how to start restoring natural capital, and why it is necessary for sustainable economic growth.