The Sun class is a class of cruise ships originally built for and operated by Princess Cruises and now operated by P&O Cruises Australia, Peace Boat, Seajets and Cheng Zhen Cruises. The vessels in the class were designed and constructed by Fincantieri Cantieri Navali Italiani in Italy. The first Sun-class vessel, Sun Princess (now Pacific World), entered service in 1995 and the last, Ocean Princess (now Queen of the Oceans) entered service in 2000. At the time of launch, the Sun class was amongst the largest cruise ships in the world, although this has since been surpassed.
The four ships are effectively identical, with the only notable exception being the design of the bridge wings; Pacific World and Pacific Explorer having exterior bridge wings, Dream and Queen of the Oceans having enclosed bridge wings.