It will share the building on Calle Santalo with other WPP affiliate agencies Grey Group, Wunderman and Burson Marseller.
Grass Roots already has an existing operation in Madrid. Mar Garcia Ruiz, managing director for Grass Roots Spain, said: "I am excited to have Daniel joining our busy team and to deliver yet more value to our clients – especially in the promotions and incentives space.
"We have great expertise in Spain and I look forward to growing the whole business, employee solutions, customer engagement and events services included, in order to reinforce our position as market leaders."
Ian Horsham, divisional director for Promotions & Incentives, added: "The Spanish market has been difficult for the last few years, but our team in Spain has worked very hard to look after existing clients and acquire new business.
"A new site and a new appointment is a great signal of progress, locally and globally, and I have no doubt that we will be reporting further good news developments very soon."
The Grass Roots Group enjoyed its best ever trading year in 2014 and is due to announce last year’s results in the coming weeks.
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