Aldo Costa, one of the leading figures behind Mercedes' recent success, will leave the team, it has been announced.
Costa, who was engineering director before moving into a technical advisory role this year, will depart the world champions at the end of September to join Italian manufacturer Dallara.
"Since stepping back from my role as engineering director, I have enjoyed supporting the team during this season and have also been searching for my next challenge beyond Formula 1," he said.
"After many years working at the pinnacle of our sport, I am excited to be able to contribute some of what I have learned to other racing series and to high-performance automotive projects outside racing.
"One of my personal passions is to mentor and grow young talent, and it will be a focus for me to help attract and develop the next generations of Italian engineering talent at Dallara in the years ahead."
Costa joined minnows Minardi in 1988 and became technical director of the team before departing for Ferrari seven years later.
He spent 16 years in Italy, and was one of the key architects behind the Schumacher-Ferrari dominatio, as well as being chief designer during Kimi's Raikkonen 2007 title success.
The 58-year-old left Ferrari in 2011 to join Mercedes as engineering director, and has added another 10 world championships (five drivers' and five constructors') to his honours, including four titles for Britain's Lewis Hamilton.
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Mercedes team principal Toto Wolff added: "Aldo has been one of the pillars of our team since he joined in 2011 and he now leaves us with the same dignity and professionalism that have characterised his years with us.
"His new role with Dallara is a fantastic opportunity and I am delighted he has found such a rewarding role in which to pursue his career - and to contribute his knowledge to almost every level of global motorsport."
Dallara have a rich motorsport heritage, and are currently involved with the building of cars in IndyCar, Formula Two and Formula Three. Costa will start work for them in 2020.
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