Collector is the second Japanese-language studio album and third overall by South Korean girl group Itzy. It was released on October 8, 2025, by Warner Music Japan. The album features 10 tracks, including the lead single "Rock & Roll", and Japanese versions of the previously released singles "Imaginary Friend", "Girls Will Be Girls", and "Gold". It also features "Algorhythm" and "No Biggie" (2024) re-recorded as a quintet.
On August 22, 2025, it was announced that Itzy would release their second Japanese studio album, Collector, on October 8. The announcement was accompanied by a series of teaser images featuring the members in pastel-colored outfits, a concept also reflected in the album's digital cover. Collector was made available in eight different physical formats, each including a CD. Two limited edition versions were also released: one including a DVD and another featuring two sets of four-cut photo strips.