Sanctuary is the fifth extended play (EP) by South Korean girl group Lovelyz.

[2] Promotion for the album began with the release of individual teasers of members and the short version of music video teaser through the group's official accounts on Twitter, Facebook, and YouTube from November 15 to November 20.

The title track "Lost N Found" was revealed with the release of the album's tracklist on November 21.

The next day, Lovelyz released a longer version of the music video teaser for "Lost N Found".

[6] Lovelyz held their comeback showcase at Yes24 Live Hall on November 26, 2018,[7] the same day as the album's release.