Within the UK organisation there will be three divisions.
GfK NOP Custom Research, headed by former NOP chief executive Phyllis Macfarlane, will bring together research sectors of NOP Research Group and GfK Martin Hamblin, including automotive, business-to-business, consumer, financial, technology, social research and mystery shopping.
GfK Healthcare combines NOP Healthcare and GfK Martin Hamblin Healthcare. The division will be headed by former head of research at NOP World Health, David Bayton.
GfK NOP Media brings together NOP World Media and GfK Media and will be headed jointly by former NOP media divisional director Joanne Wilbraham and former director of GfK Media UK, Nick North. The group will not be formed until the end of the year.
Petra Heinlein, chief executive of GfK's custom research board worldwide, said: "Each company can now focus its energies on strengthening the services within its own geography, to ensure clients benefit from the powerful mix of industry experts and research know-how."
NOP World was bought from United Business Media for £383m in April. The combined holdings make the organisation the fourth-largest custom research business in the world.
There are an extra 1,500 NOP employess working at GfK, with both companies bringing in joint sales of almost €1bn (£682.7m) in 2004.
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