Agriculture employs almost 50% of the population but makes up only 10% of the gross domestic product. Rice is by far the leading commercial crop, followed by rubber, corn, sugarcane, coconuts, and soybeans. Thailand's teak, once a major export, is still a valuable commodity. Marine and freshwater fisheries are important; fish provide most of the protein in the diet, and some of the deep-sea catches (mackerel, shark, shrimp, crab) are exported. Thailand is also a major exporter of farmed shrimp. Tin and tungsten are the most valuable minerals and major export items. Lead, zinc, and antimony are also mined for export. Iron ore, gold, precious and semiprecious stones (especially saphires and rubies), salt, lignite, petroleum, natural gas, asphaltic sand, and glass sand are exploited on a smaller scale.
Thailand has substantial hydroelectric potential, which is being developed; projects have been constructed on the Ping, Mekong, Phong, and Songkhram rivers. Industry is growing. Much industry is focused on the processing of agricultural products; rice milling is by far the most important, followed by sugar refining, textile spinning and weaving, and the processing of rubber, tobacco, and forest products. The manufacture of electrical and electronic equipment, including appliances and computers and integrated circuits, became important in the late 20th cent., causing a substantial rise in the per capita gross domestic product. Lumbering is concentrated in the north. Other industries include steel production, oil refining, tin smelting, vehicle and machine assembly, and vehicle parts. Small factories, many of which are in the Bangkok area, manufacture jewelry, furniture, plastics, glass, and pharmaceuticals. Tourism is the leading source of foreign exchange, and handicraft production has a ready market in the tourist trade. Thailand is also a major transshipment point for illicit heroin and has become a drug-money-laundering center. The main exports are textiles and footwear, fishery products, rice, rubber, computers and electronics, automobiles and auto parts, electrical appliances, and jewelry. The chief imports are capital and consumer goods, raw materials, and fuels. The main trading partners are Japan, the United States, China, Malaysia, and Singapore.
Bangkok is a key point on round-the-world air routes. It is the political, commercial, cultural, and transportation center of the country, with the only port that can accommodate oceangoing vessels. Thailand's railroads originate in Bangkok and extend to Chiang Mai, the Korat plateau, and to Cambodia, Laos, and Malaysia; a corresponding network of paved highways has been constructed. Thailand's inland waterways—a complex, interconnected system of rivers, streams, and canals—have been important arteries since ancient times; barges and boats still carry well over half the cargo moved in the central plain.