Aerodynamicist John Iley has left McLaren to join Caterham F1, who raced as Team Lotus in 2011.
Iley will be Caterham's performance director, with responsibility for all aerodynamic design at the team.
The move reunites him with Caterham design boss Mike Gascoyne, with whom he worked at Jordan and Renault.
Chief executive Riad Asmat said Iley's appointment was "a real sign of our growth and development as a serious contender for long-term honours".
The Norfolk-based Team Lotus joined F1 as one of three new teams in 2010, finishing that season and this 10th in the constructors' championship, ahead of fellow newcomers HRT and Virgin.