Rainbow (stylized as RAINBOW) is the fifth studio album by Japanese recording artist Ayumi Hamasaki, released on 18 December 2002 by Avex Trax. Production of Rainbow had commenced after the release of Hamasaki's fourth studio album I Am... that January; All lyrics were written by Hamasaki, and Japanese producer Max Matsuura returned to produce the album. Hamasaki increased. The album was Hamasaki's first to feature conversational English lyrics, where in her previous works she had only used single words.