Kirby Corporation, through its subsidiaries, conducts operations in two business segments, marine transportation and diesel engine services. The companys marine transportation segment is engaged in the inland transportation of petrochemicals, black oil products, refined petroleum products and agricultural chemicals by tank barges and, to a lesser extent, the offshore transportation of dry bulk cargo by barge. Its diesel engine services segment is engaged in the overhaul and repair of diesel engines and reduction gears and related parts sales in three markets, the marine market, the power generation and industrial market and the railroad market. Kirby Corporation is headquartered in Houston.