"A BEST" is the first "best of" album released by Hamasaki Ayumi. There is some controversy surrounding this album as it has the same release date of Utada Hikaru's Distance album, thus staggering the sales of both albums. Whether avex intentionally pushed the release of this album to be at the same time as Distance remains a controversial topic. It is also rumored that the cover image, depicting Ayumi with a tear rolling down her cheek, was chosen by her as a protest to the false media reports that she and Utada are personal rivals.

The songs "A Song for ××", "Trust" and "Depend on you" were re-recorded for this album along with "End roll," which wasn't anounced to be re-recorded, and "Boys & Girls," which had a new instrumental part but the voice still being the same as the older version. Though this was her best selling album, Hamasaki Ayumi opposed of it publicly, stating "it was too early for release". This album sold more than 4,300,000 copies to date. The album reached #1 on the Oricon Album Charts and charted for 48 weeks. A BEST was re-released the same day as for A BEST 2 -BLACK- and A BEST 2 -WHITE-...