Kozo Ohsone (大曽根 幸三?, 1933-11-10) is the Japanese manager for Sony who was credited as one of the main developers of the Walkman. While general manager of the Tape Recorder Business Division he was asked to help develop a portable audio player. Ohsone and his staff modified the existing Pressman device to create the Walkman, which was released in Japan in 1979.