Fortune 1000 rank: 16
Best Companies rank: 22
No. of U.S. employees: 18,730
Most common salaried job (Avg. Pay):
IS Specialist ($86,915)
What makes it so great? Refineries can be dangerous places; of the 23 refineries designated by OSHA as having the best safety programs, 11 are Valero units. Another plus: The company has never laid off a single employee.