Concentration 20 is the third studio album by Japanese singer Namie Amuro. It was released on July 24, 1997, by Avex Trax. The album's genre is a fusion of styles including pop, dance, rock, reggae and ska. Unlike Amuro's previous effort, Sweet 19 Blues, which primarily had lyrics written by Tetsuya Komuro, Concentration 20's lyrics were mostly written by Marc Panther. Komuro did, however, compose and arrange most of the album's songs and wrote the lyrics to three of them. It was Namie's second solo album since splitting up with Super Monkey's.

Namie Amuro is a retired Japanese singer. She rose to prominence as a teen idol, and transitioned into a leading pop artist due to her versatility across music styles and visual presentation. Due to her career reinventions and longevity, she is known as an icon across Japan and Asia. She has been referred to as the "Queen of Japanese Pop", and her influence domestically has drawn equivalent comparisons to artists such as Janet Jackson and Madonna in Western pop culture.