Gyakuyunyū: Kōwankyoku

Gyakuyunyū: Kōwankyoku (逆輸入 ～港湾局～; "Reimport: Ports and Harbours Bureau") is an album by Japanese musician Ringo Sheena, released on May 27, 2014. It is a self-cover album, featuring new recordings of songs that Sheena wrote for other artists.

Each song also collaborates with a different famous Japanese music producer. Gyakuyunyū was the final release of Sheena's 15th anniversary celebrations, released on the day marking 16 years since her debut single "Kōfukuron".

"Gyakuyunyū" (逆輸入, literally "reverse import", commonly rendered as "reimport") in the title refers to the act of reimporting products that were once exported to another country, and by extension, it also applies to culture and technology. Editor/Writer Masaki Uchida offered further explanation in the liner notes that "reimported" products are often regarded as containing rare items, as they are originally manufactured in accordance with the market conditions and regulatory frameworks of their export destinations or production sites. Consequently, their specifications and performance often diverge from those of domestically marketed counterparts. Such differences may manifest in distinctive outputs, designs, or color variations in automobiles, motorcycles, apparel, wristwatches, and consumer electronics, thereby creating opportunities for enthusiasts to encounter items of substantial or exceptional rarity.