"Keep the faith" is the fifth overall single by the Japanese boy band, KAT-TUN, and the second from their third studio album, KAT-TUN III: Queen of Pirates. It was released in three editions with three different covers; the regular edition contains all the songs and its instrumental versions, the first press edition came with a bonus track entitled "Lovin'U" and its instrumental track and the second limited edition was packaged with a DVD with the single's music video and a short film about the making of the music video.

Kyosuke Himuro is a former Japanese musician and singer-songwriter. He was the lead vocalist of the rock band Boøwy from 1981 to 1988. After the band disbanded, he went on to have a successful solo career, becoming one of Japan's best-selling artists. In 2003, HMV Japan ranked Himuro at number 76 on their list of the 100 most important Japanese pop acts. He currently lives in Los Angeles, California.