Accountability score: 75.2
2006 rank: 2
Global 500 rank: 4The world's second-biggest company reclaims the top spot on our list from Vodafone, the leader on last year's list. BP has led its industry in the research and development of wind, solar, and carbon-dioxide sequestration technologies. But new CEO Tony Hayward's core focus is getting new oil and gas projects online, like fields in Azerbaijan, Angola, Indonesia, and the Gulf of Mexico. That pleases shareholders and helps to lower prices for consumers through increased supply - a goal BP considers a core part of its social responsibility. Despite two years of major accidents - a pipeline spill in 2006 and a refinery explosion in 2005 - BP earned points for replacing several executives at those businesses.