Kirby Corporation, based in Houston, Texas, operates inland tank barges and towing vessels transporting petrochemicals, black oil products, refined petroleum products and agricultural chemicals throughout the United States' inland waterway system. Kirby also owns and operates four ocean-going barge and tug units transporting dry-bulk commodities in United States coastwise trade. Through the diesel engine services segment, Kirby provides after-market service for medium-speed and high-speed diesel engines and reduction gears used in marine, power generation and railroad applications.