Esomar, the market research organisation, said that there were 88 acquisitions last year, leading to the dominance of the top 10 firms.
In its Global Market Research Report for 2005, published to coincide with the Esomar Congress this month, it found that the global industry now has a turnover of $23.3bn (拢12.3bn), representing growth of 5.7% on 2004.
Europe continues to dominate representing 45% of the market at $10.4bn, followed by North America at $8.3bn -- a share of 36%.
The research showed how the growth of online research was changing the face of the industry. It revealed that face-to-face interviews -- although still the most popular research method -- decreased by 7% since 2004 and now represent 24% of data collection. Telephone interviews remain popular at 21% showing a slight growth worldwide of just 1%.
Veronique Jeannin, Esomar director-general, said: "We expect the market research industry's healthy growth rate to continue in the near-term driven by good economic conditions, increasing client demand for continuous multinational research projects and value added research based consultancy."
VNU is the biggest market research firm in the world, followed by Taylor Nelson Sofres. US healthcare firm IMS is third and the merger of GfK and NOP makes it the fourth-biggest market research group in the world. Kantar is at number five.
Other UK firms to make the top 25 include Ipsos Group, formed by the merger of Ipsos and Mori, ranked at six; and Aegis Group-owned Synovate at number eight.
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