When American designer Henry Dreyfuss began work as a consultant to Bell Telephone Laboratories (BTL) in 1930, he sought simplicity and unity of form in the installations of their equipment. He persuaded BTL to let him work with their engineers, and this collaboration resulted in the 302 telephone of 1937. The unified and balanced form of the 302 replaced the awkward and ungainly shapes of earlier models. Its successor, the 500 of 1949, was a response to the increased post-war demand for telephone service. Since telephones were leased, the new design needed to be easy to service and have an unobtrusive appearance. Manufactured from a less brittle plastic, the 500’s handset was lighter, and its shape allowed the user to cradle it against his or her shoulder. Nearly fifty years later, the handset is widely used for public telephones in the United States. The next major innovation, the Trimline (1965), placed all of the controls in the user’s hand. Dreyfuss’s sensitivity to consumer needs and his desire for a telephone that would suit most home environments guided many of the developments of BTL’s equipment.