Paddy Lowe is to start with Mercedes next month after being granted an early release from his contract with McLaren.
Lowe had been expected to make the switch at the end of the year, having been replaced by Tim Goss back in February
ahead of him taking on a 'fresh challenge' for 2014.
However, agreement has now been reached for Lowe to be released from his contract with McLaren ahead of schedule in order to take up a new position with Mercedes on 3 June.
"I am excited to become part of a highly talented and capable technical organisation,” Lowe said. “The team has already produced probably the fastest car of the 2013 season while the technical challenges of the new regulations for 2014 will give us the opportunity to maximise the synergies available to a works manufacturer. That is a challenge I am relishing.
“I have worked closely with Mercedes-Benz for almost 20 years and deeply admire the company's phenomenal commitment to Formula One. I look forward to much success together in the years ahead."
Lowe will become the Executive Director (Technical) at the Brackley-based team and will work closely with Mercedes motorsport boss Toto Wolff and Ross Brawn, the team's Executive Director (Business).
Brawn will retain overall responsibility for technical and sporting matters in his role as team principal.
"I am delighted to welcome Paddy to the team and to begin working together,” he said. “He has an excellent record of success in the sport and would be an asset to any of our rivals in the pit lane. It is no secret that every team is facing a significant balancing act between this year and next.
“But it is perhaps less obvious that we will also see major changes for the 2015 and 2016 seasons, as development progresses with the new generation of car design and Power Unit. To deliver in these circumstances, a successful team needs strength in depth. Paddy's arrival will further strengthen our organisation and puts us in a strong position for the future."