Replacing outgoing design director Frank Stephenson, Melville will report directly to McLaren chief operating officer, Dr Jens Ludmann.
"I remember when I got the call to come and join McLaren back in 2009 and the joy I felt then is the same today. We have developed a fantastic design team and have integrated a design philosophy that I feel passionately about," Melville said.
The British designer's latest appointment follows his promotion to chief designer in 2014, reporting to Stephenson.
Melville has already played a key role in McLaren's rapid ascendance to the top end of relatively high-volume supercar production, having established the brand's "design pillars" - the starting point and guiding principles for every McLaren car.
"These pillars form the main ethos from which the team create breath-taking products that tell the visual story of their function. Implemented under Rob’s direction, the design pillars outline the core design principals of everything for a reason, functional jewellery, truth to materials, perfect proportions and always to be brave," McLaren says.
In his new and more senior role, Melville will work more closely with engineering and manufacturing divisions at McLaren, and the company's customer insights teams - all freeing Melville to interpret the needs of each branch in his own view, rather than taking direction from Stephenson.
Of course, you've already seen Melville's work: he was responsible for the new McLaren look introduced with the 720S revealed in Geneva earlier this year.
From there, Melville did a stint with GM, where he developed new design principles for Cadillac, taking a leading hand in the design of the Converj concept. Unlike the Evoque, however, the production version of the Converj - the Cadillac ELR - did not win many friends.
The news of Melville's promotion follows a decision by current design director Frank Stephenson (above) to leave the company, which came with no explanation and no confirmation of a new role elsewhere.
Reports in recent weeks, however, have hinted that Stephenson may soon reappear at Mini, where he kickstarted the brand's revival under BMW with the design of the first new-generation Cooper in 2001.
Mini has been without a styling head for sometime now, with Danish designer Anders Warming leaving the business in July 2016 to lead the look of the reborn Borgward brand.
Stephenson returning to Mini would likely mean more of the same for the now German-owned brand. After leaving the company in 2002 - not long after his first Cooper debuted - he moved to Fiat to design the 500 hatch still kicking around today.
Of course, Stephenson's work with McLaren, and on designing the beloved Ferrari 430, shows he is a broadly talented designer. Could he deliver a shakeup for the Mini brand?
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