Trono fills a vacant role at the agency, which bought the UK agency Grand Union in 2010. The former executive creative director of Grand Union Becky Power left in February 2013.
In his new role Trono will have responsibility for the creative department and direction at the main FullSIX agency, as well as Grand Union, which continues to operate as a conflict shop.
As executive creative director, Trono will report to chief executive Hugh Bailie, who joined FullSIX in January after leaving the startup agency Hello People, which he co-founded. Hello People subsequently closed.
Trono will be responsible for bringing together FullSIX’s retail, data, profile and search experience to offer "cost-effective" digital solutions for clients.
He will also hire new staff to expand the creative team.
Trono had been in his role at Publicis Chemistry for six years, including during its name change when Publicis acquired the original agency Chemistry in 2011. Before being promoted he was a senior creative at Chemistry.
Baillie says: "Rob combines an entrepreneurial spirit with a deep knowledge of the digital space. He has a great relationship with technology but comes at it with ideas first.
"His track-record with brands and his ability to mine for the best nuggets of opportunity on their behalf is outstanding. I am looking forward to working with him and taking FullSIX London forward to the next stage in its development."
Trono said he was attracted to FullSIX because of its independent ownership and because it had a wealth of talent and experience with the dynamic drive and ambition of a start-up".
Baillie has also made recent promotions to FullSIX’s management team, including the former business director Sophie Spray, who has been promoted to the client service director with overall responsibility for FullSIX’s Sainsbury’s account.
Nicola Borradaile, another business director, has been promoted to the new business director, while Tony Mohammed, the head of business development, becomes the European business development manager.
The planning director, Adrian Gans, the technical director, Andrew Dobson, and the UX director, Sundeep Kumar, all continue in their roles and complete the management line-up.