Adrian Martin Newey (born 26 December 1958) is a British engineer, aerodynamicist, automotive designer, and motorsport executive. Since 2025, Newey has served as technical director and co-owner of Aston Martin in Formula One; he previously served as technical director of Leyton House and McLaren, chief designer of March and Williams, and chief technical officer of Red Bull Racing. Widely regarded as one of the greatest engineers in Formula One history, Newey's designs have won 14 Drivers' and 12 Constructors' titles and 223 Grands Prix between 1991 and 2024.

After designing championship-winning Formula One cars for Williams and McLaren, Newey moved to Red Bull in 2006, his cars winning the Formula One Drivers' and Constructors' titles consecutively from 2010 to 2013, the Drivers' Championship in 2021, and both titles in 2022 and 2023. The Newey-designed RB19 is the most successful Formula One car in history, winning 21 out of the 22 races (95.45%) in which it competed. Newey's designs also won the 1985 and 1986 CART titles. On 1 May 2024, Red Bull Racing announced that Newey would leave his day-to-day Formula One design duties immediately and shift his focus to the RB17 hypercar (2025). Newey fully left the company in the first quarter of 2025.

Adrian Martin Newey was born in Colchester, Essex, England, on 26 December 1958, the son of Richard and Edwina Newey. His father was a veterinarian and his mother was an ambulance driver during the Second World War. He attended Repton public school alongside motoring journalist and writer Jeremy Clarkson. Newey was asked to leave Repton at the age of 16 after an incident at a Greenslade concert at Repton's 19th-century Pears School Building organised by the school's sixth formers, where he pushed up the sound levels on the band's mixer, cracking the building's stained glass windows.

Newey gained a first class honours degree in Aeronautical Engineering from the University of Southampton in 1980. Immediately after graduation, Newey began working in motorsport for the Fittipaldi Formula One team under Harvey Postlethwaite. In 1981, he joined the March team. After a period as a race engineer for Johnny Cecotto in European Formula 2, Newey began designing racing cars. His first projects were the March 82G and 83G sports cars to compete in the IMSA GT Championship. The latter was highly successful and won the IMSA's title in 1983 and 1984.

In 1984, Newey moved to the March Indy car project, working as designer and race engineer for Bobby Rahal at Truesports. Newey formed a close friendship with Rahal, which would impact their careers some fifteen years later. Newey's March 85C design won the 1985 CART championship in the hands of Al Unser, and the 1985 Indianapolis 500 with Danny Sullivan. In 1986, Newey moved to Kraco to engineer Michael Andretti's car, while his March 86C design won the 1986 CART championship and 1986 Indianapolis 500 with Bobby Rahal. At the end of 1986, Newey joined the Haas Lola Formula One team in an effort to improve its fortunes, but the team withdrew at the conclusion of the 1986 season. After a spell at Newman-Haas in 1987 working as Mario Andretti's race engineer, Newey was re-hired by March, this time to work in Formula One as chief designer.

Newey's first Formula One design, the 1988 March 881, was far more competitive than many expected, with Ivan Capelli finishing second in Portugal, and even passing Alain Prost's McLaren-Honda turbo for the lead of the 1988 Japanese Grand Prix briefly on lap 16. As March became Leyton House Racing in 1990, Newey gained promotion to the role of technical director. At the 1990 French Grand Prix, Capelli led the most part of the race and finished second after a late pass by Prost's Ferrari, but that proved to be the year's bright spot, with the team's results declining. In the summer of 1990, Newey was fired, although he soon found another role. Newey later said: "I was fired but I'd already made up my mind I was going – because once a team gets run by an accountant, it's time to move. Your self-confidence does suffer but Williams had approached me."

Through the 1980s and into the 1990s, Williams was a top running team, and technical director Patrick Head wasted no time in getting a contract signed. With a vastly superior budget, drivers, and resources at his disposal, Newey and Head rapidly became the dominant design partnership of the early 1990s. By mid-season 1991, Newey's FW14 chassis was every bit a match for the previously dominant McLaren, but early season reliability issues and the efforts of Ayrton Senna prevented Williams team leader Nigel Mansell from taking the title. In 1992, there would be no problems, and with dominance of the sport not repeated until the 2000s Ferrari years of Michael Schumacher, Mansell took the Drivers' title and Newey secured his first Constructors' title. 1993 delivered a second, this time with Alain Prost at the wheel of the FW15C.

1994 saw a rare dip in performance for Newey-designed cars and the team and drivers struggled to match Schumacher and the Rory Byrne-designed Benetton B194 for pace and reliability. Disaster struck at the 1994 San Marino Grand Prix with the death of Senna who had joined Williams that year. A late-season charge, helped by a two-race ban for Schumacher, enabled Williams to claim their third straight Constructors' title; however, Williams were unable to take a third consecutive Drivers' title, and with possible manslaughter charges for Senna's accident in prospect, cracks began to show in Newey's relationship with Williams team management.