Location: Canada
Year founded: 1917
Revenue: $13.6 Billion
Employees: 5,500
Measures the environmental impact of each project. Finding black gold is a dirty job - particularly when it's buried in tar sands. But Suncor still stands out for how it does the job. Its environmental and social efforts have earned it membership in the Dow Jones sustainability index and the British equivalent, the FTSE4Good. In a survey of 23 global oil companies last year, Jantzi Research, a Canadian consultancy, named Suncor a top performer, noting its environmental and greenhouse-gas management programs. Specifically, it has improved emissions intensity (the amount of oil it extracts per ton of greenhouse gases emitted) 25 percent since 1990. Ditto for energy, sulfur dioxide and nitrogen oxide. Suncor is part of an initiative to develop carbon-capture techniques. And while Suncor hopes to double its production by 2012, its water management is so advanced that it expects to draw no additional water from Alberta's Athabasca River. --Cait Murphy