Concentration 20

Concentration 20 is the third studio album by Japanese singer Namie Amuro, released July 24, 1997, by Avex Trax. The album's genre is a fusion of styles including pop, dance and rock. 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 the beginning in 1997.

"A Walk in the Park" was released as the album's lead single on November 27, 1996. It was very successful, becoming Amuro's fourth number one single and fourth million-seller. The second single, "Can You Celebrate?", was released on February 19, 1997. It was an unprecedented commercial success, selling over 2.7 million copies and remains the best-selling physical single by a female soloist in Japanese history. It was certified double million by the RIAJ, her first and only single to receive such a certification. The rock-infused third single, "How to Be a Girl", reached number one and sold over 770,000 copies, becoming Amuro's sixth number one single.

The album received positive reviews upon release and won the Asia Association Music Prize Awards. The album was massively successful, premiering at the top of the Oricon albums chart with first-week sales of 824,980 copies. It resided on the charts for 28 weeks, and was the seventh best-selling album of the year, selling nearly two million copies and is the 83rd best selling album of all time in Japan. Combined with the sales of its singles, Concentration 20 has sold around 4.5 million copies.