The European office has been set up to service the agency's client car client Hummer across the Europe and Middle East regions.
Simmonds managed account teams on pan-European and global clients at W&K, where he worked for nine years, including Coca-Cola, Microsoft, Nike, Vodafone, Siemens Mobile Devices and Audi at W&K.
Prior to moving to Amsterdam, Simmonds worked in London with Publicis as a group account director.
The agency is now set to hire an executive creative director for the Amsterdam office, until then Modernista! founding partners and executive creative directors Gary Koepke and Lance Jensen will take hands-on responsibility for the start-up.
In a joint statement, Koepke and Jensen, said: "This is a very exciting and carefully thought out step for Modernista!.
"It will enable us to better service brands with aspirations beyond the US marketplace, such as Hummer."
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