Gauteng is the biggest contributor to South Africa's GDP, with Logistics & communication, financial services & mining are the biggest sectors.
Gauteng is an integrated industrial complex with major areas of economic activity in five subregional areas, namely the Vaal Triangle, the East, West and Central Rand, and Pretoria. All sectors rely heavily on the Vaal Dam on the Vaal River, whence water is piped across the province.
There are about 10 000 firms involved in the province's manufacturing sector, employing over half a million people. The major industries are appliances and electrical supplies, basic iron and steel, chemical products, electrical machinery, fabricated and metal products, food, machinery, motor vehicle parts and accessories.
The economy of the province is moving away from traditional heavy industry markets and low value-added production to sophisticated high value-added production, particularly in information technology, telecommunications and other high-tech industries. The 'high-tech' corridor at Midrand (halfway between Pretoria and Johannesburg) is the most rapidly developing area in the country.
The JSE Securities exchange (the largest in Africa) has its home in Sandton, Johannesburg.