The acquisition, Golley Slater's third of the year, will also give the agency a foot in the door with T2's existing clients, including T-Mobile and American Express.
As a result of the deal, T2 will be rebranded as The Business Strategy Group and moved into Golley Slater's Covent Garden premises.
Chris Lovell, chief executive of Golley Slater, said: "This is another strategic acquisition for Golley Slater. It complements and strengthens our existing businesses. Many of our clients already utilise contact centre services and we are keen to develop our expertise further in this area, providing even more return on investment for our clients."
T2 was founded by Derwyn Jones and Gary Slade, who will remain in charge of the business at Golley Slater. The company specialises in building and managing contact centre operations in the UK, Europe, the US and India.
Golley Slater comprises 14 marketing companies in nine offices across the UK and has an annual turnover of over 拢45m.
Last month, it launched a promotional marketing division headed up by former Yellow Submarine directors Cal Ledward and Eileen Neale.
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