"A World to Believe In" (Japanese: あなたがいる限り, Hepburn: Anata ga Iru Kagiri, "As Long as You are with Me")[1] is a song recorded by Canadian singer Celine Dion, taken from her tenth English-language studio album, Taking Chances (2007).

The track was re-recorded in October 2007 as an English-Japanese duet with Yuna Ito, retitled as "あなたがいる限り: A World to Believe In."

[6] "A World to Believe In" follows Ikimono-gakari's "Akaneiro no Yakusoku" to become the ninth LISMO cellphone service TV commercial song, aired from 1 December 2007.

"あなたがいる限り: A World to Believe In" (U.S.A. mix) subsequently appeared as the first track on Dion's greatest hits album, called Complete Best, released on 27 February 2008.

The melody of "A World to Believe In" was re-composed and the Japanese lyrics were added for the film Maboroshi no Yamataikoku, which stars Sayuri Yoshinaga.