By the early 20th century, Cartier had expanded its collection to include watches. At a time when pocket watches were still considered de rigueur for the distinguished gentleman, Cartier helped popularize the wristwatch, making it a bold fashion statement for men and women as well as a status symbol among the well-to-do. Louis Cartier is credited with creating the first men's wristwatch, the Santos, in 1904. He developed and named the watch for his client and friend, the Brazilian aviator Alberto Santos-Dumont, who needed a device that would allow him to read the time without taking his hands off the controls of his airplane.

Other classic designs followed, including Cartier's signature timepiece--the Tank--which debuted in 1917 during the First World War and was inspired by the tough new war machine the Americans introduced to the fighting in Europe. Cartier's first water-resistant watch was named after the Pasha of Marrakesh, who requested that Cartier create watch that he could wear while in his swimming pool and not lose track of time.

And while it is known more for its luxurious design, Cartier is also credited with creating the highly functional deployment folding clasp in 1910, which is now used by watchmakers around the globe.

Modern Cartier watchmakers still base their watch designs on the early fundamentals developed by Louis Cartier. Treasured by collectors, Cartier watches are distinguished by their impressive variety of shapes (round, square, oval, Tank, Tortue and Tonneau), by their exceptional materials and workmanship, and by their recognizable Cartier aesthetic, an elegant blend of classic and modern design.