Phorm has appointed Daniel Park, formerly senior vice-president of the search and portal division at SK Communications, as CEO of Phorm Korea and has opened an office in Seoul.
Korea has approximately 15m broadband customers, according to the Organisation for Economics Co-operation and Development, making it the sixth largest broadband market in the world.
KT is the leading ISP in Korea with an estimated market share of 44%.
In addition to its activity in Asia, Phorm has already signed exclusive agreements with UK ISPs BT, TalkTalk and Virgin Media.
Kent Ertugrul, founder and chief executive of Phorm, said: "Just as KT has led the way in helping to create one of the world's leading online societies, we believe that today's announcement will put Korea at the forefront of a new revenue model for the internet which creates exciting opportunities for all concerned.
"This system promises to boost the value chain that connects consumers, content creators and advertisers. We also believe that this technology offers a new model for online privacy by demonstrating how users can browse in complete anonymity, with no storage of browsing history while showing offers which they find useful."
Earlier this month Phorm appointed Telegraph Media Group's former digital general manager, Mike Moore, as its global commercial director.