The Ministry of Information and Communications (MIC) was formerly responsible for the provision of all telecommunications services in South Korea and on the country's behalf internationally and is now the industry legislator. Industry regulation is conducted by the Korean Communications Commission, established in 1992. KT Corporation - then known as Korea Telecommunications Authority (KTA) - was formed in December 1981 to take over the provision of telecommunications services from the ministry, as part of the government's Fifth Five-year Economic and Social Development Plan. Shortly thereafter, in March 1982, Datacommunications Company of Korea (DACOM) was set up and was initially licensed to provide data communications services. Its licence has since been expanded to encompass international services, domestic long-distance telecommunications networks, value-added services, and multimedia facilities. Through its stake in Hanaro Telecom, the company also provides local telephony services. Hanaro Telecom launched local telephony services in April 1999 and its licence was expanded in December 2002 to allow it to directly provide domestic long-distance and international telecommunications services. DACOM was awarded its own licence to provide local telephony service in July 2004, and began offering a pilot service in November 2004, with national rollout planned by 2009.

KT Corporation provides mobile services through its 47% stake in KTF (an entity formed by the mergers of KT Freetel, KT M.Com, and KTICOM). The leading wireless operator is SK Telecom, which merged with fellow cellular operator Shinsegi in mid-January 2002. ONSE Telecom, the country's fourth fixed operator, launched international services in October 1997.

The market saw further movements towards consolidation in 2003, with Hanaro renewing its bid for the ailing Korea Thrunet and having almost completed the integration of DreamLine, which it had acquired during 2002. Also in 2003, ONSE Telecom filed for court receivership, emerging as a restructured entity in December 2003. Hanaro and DACOM continued their battle for ownership of Thrunet during the remainder of 2003 and throughout 2004, with Hanaro emerging victorious in February 2005.