Book excerpt: Opportunities Beyond Carbon presents climate change as potentially the 'best crisis we ever had'. It maps the many opportunities for communities large and small, local and international, making the transition to a low carbon economy. John O'Brien has compiled essays by key politicians, investors, business people, activists and academics on how to make the most of the current predicament. This fresh, lucid and practical optimism for the future offers a foundation for an entirely new and proactive attitude to climate change.