Between 1934 and 1938 he was the designer for French coachbuilder Marcel Pourtout. Among his designs were a Panhard coupe, a Unic cabriolet, a Delage D8, the “water drop” Talbot-Lago, the Darl'mat Peugeot roadsters used in 1937 and 1938 at Le Mans. Richard Adatto, author of a book on French aerodynamic styling of the era, has been quoted as saying: "Paulin became the leading French stylist of the time... Everything he touched was designed with aerodynamics in mind. He was very conscious of fuel efficiencies and the aerodynamic efficiencies that could be created by the lines of the car. You could go faster, which meant you could put a smaller engine in the car and it could go faster even though it was a small car."
Pourtout, Emile Darl'mat, and Paulin collaborated in the creation of the revolutionary Eclipse roof, the first power-operated retractable hardtop, which was patented by Paulin in 1931 and in 1934 was used in the Peugeot 402BL Éclipse Décapotable, a small coupe. Carrosserie Pourtout produced Eclipse versions of the Peugeot 301, 401, 402 and 601, the Lancia Belna, and models from Hotchkiss and Panhard.
In July 1940, while he was an engineer at Avions Kellner-Béchereau, Georges Paulin began working with British Intelligence to fight the Nazis. Discovered by the Gestapo thanks to French Vichy elements he was arrested in 1941 and condemned to death by a German military tribunal. He was executed March 1942. An escape plan had been arranged by the British, but Paulin declined to use it, and sacrificed himself in order to protect his team.