The costs of global warming, extreme weather, pollution and other forms of “environmental debt” are wreaking havoc on the economy, argues Amy Larkin. In Environmental Debt: The Hidden Costs of a Changing Global Economy she proposes a new framework for 21st century commerce, based on three principles: 1) Pollution can no longer be free; 2) All businesses should take the long view; and 3) Government must play a vital role in boosting clean technology and growth while protecting the environment.