The CST was founded in December 20, 1989 and started its commercial activity on 01 January 1990. It is a global telecommunications operator in the form of Public Limited Limited Liability Company, mixed capital allocated over Africatel Holding BV which owns 51 % and at Santomense State holding 49%. Pioneer in the STP market, first with a fixed analog and later network with fixed and mobile digital networks GSM, with valid operating licenses until March 1, 2027. Innovation and proximity to the customer are the main CST's operating lines. Technological innovation, relational innovation, communication innovation, service innovation and a close attitude to the customer, aiming it as a partner