The media group has bought a 51% stake in Agency W from its owner Jong Lyul Baik. The agency will become part of Isobar, Aegis' recently launched digital network.
It is not the group's first move in the country -- two years ago its media buying agency Carat opened an office in Korea in an attempt to capitalise on its win of the consolidated media-planning and buying account for Korean car giant Hyundai.
Aegis has paid an initial £200,000 for the stake in Agency W, which has clients including Korea Telecom, Adidas, Daewoo and L'Oreal.
The total payable could rise to £2m over four years depending upon the performance of Agency W over that period.
Agency W was launched in 1999, having previously been a division of Korea Telecom. The agency offers planning, web strategy, online planning and buying and CRM services.
Doug Flynn, chief executive of Aegis Group, said: "The acquisition of Agency W is consistent with our strategy of investing in the Group's strong global networks. We are very impressed with the vision of Agency W and we welcome it to the Isobar network."
As well as Aegis, WPP Group has been busy expanding in Korea. Its recent shopping spree has included LG Ad and Diamond Ad, two of Korea's biggest players, giving WPP a quarter of the market.
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