McDonald’s promises to use only beef, coffee, fish, chicken, and cooking oil obtained from sustainable sources. Coca-Cola promises to achieve water neutrality. Unilever has set a deadline of 2020 to reach 100 percent sustainable agricultural sourcing. Walmart has pledged to become carbon...

The recent financial crisis shook not only the global economy but also conventional wisdom about economic policy. After the collapse of Lehman Brothers in September 2008, policy makers reversed course and acted on an unprecedented scale. The policy response was remarkable both for its magnitude...