Masayo Sakai is a Japanese composer and musician, known primarily for her work in the video game industry during the 1990s as a member of the Namco Sound Team. Her most celebrated and influential work is the soundtrack for the racing video game *R4: Ridge Racer Type 4* (1998) for the PlayStation. For this title, Sakai created a sophisticated fusion of acid jazz, funk, drum and bass, and house music that defined the game's aesthetic and is still considered a genre classic, widely acclaimed by critics and the public. In addition to *R4*, she made significant contributions to the music of other successful Namco titles, including *Tekken 3* and *Ace Combat 3: Electrosphere*, demonstrating remarkable stylistic versatility. Her style, characterized by elegant melodies and immersive atmospheres, has earned her lasting recognition as one of the most important composers of her generation. After leaving Namco in the early 2000s, she continued to work as a freelance composer.