Kirby Corporation is the largest domestic tank barge operator in the United States, operating an extensive fleet of inland and coastal tank barges that transport bulk liquid products such as petrochemicals, refined petroleum, and black oil through the nation's waterways and coastal regions under long-term and spot contracts. The company's Marine Transportation segment generates revenue through term and spot contracts with customers who benefit from the cost and environmental advantages of barge transport compared to rail and trucking alternatives. The Distribution and Services segment operates service centers and manufacturing facilities across multiple states, providing engine and equipment overhaul, repair, parts supply, power generation systems, and specialized oilfield equipment primarily to commercial, industrial, power generation, and oil and gas customers.