Still, on its 22 ships, Royal Caribbean has amassed a nearly $120 million collection of works by mostly mid-career and emerging artists.

Among pieces that have drawn buzz is Dream of Utopia, an installation by Korean artist Keysook Geum, which fills the aft elevator lobby on Allure of the Seas with 34 dress shapes made of crystal beads and wire that appear suspended in space.

Also on Allure are whimsical sculptures by Romero Britto, a Miami-based pop artist, who also has a shipboard store where passengers can buy items featuring his designs.

Specially commissioned works on sister ship Oasis of the Seas include a poignant installation of 1,500 glass paintings on petri dishes by artist Klari Reis, who battles Crohns disease. The artwork is located in the hallway between Casino Royal and Entertainment Place.

Putting together a shipboard art collection means following certain rules, said Mariangela Capuzzo, creative director and lead curator for International Corporate Art, which buys art for Royal Caribbean, and sister line Celebrity Cruises.

“It’s an amazing experience to work on these ships. You are working on public spaces and dealing with a very specific audience. You are curating with a target in mind, to create interest and enhance the experience of cruising,” Capuzzo said. “That means no politics, no religion, no nudity.”

Art on cruise ships does not always have museum-style labeling, but passengers who want to learn more on ships operated by Royal Caribbean, Celebrity and Holland America, among others, can borrow iPads or iPods at reception for self-guided walking tours. Del Rio said Oceania will also soon have such tours. The cruise line has also commissioned a coffee table book featuring the onboard collection and is working on better labeling.

Celebrity Cruises recently cataloged its collection in a book called The Celebrity Art Collection — with a forward by Rene Morales, curator of the Miami Art Museum.

The Celebrity collection, valued at about $60 million, was begun in the 1990s when Cristina Chandris, the art-loving wife of then-owner John Chandris, decided modern cruise ships should highlight top-flight modern and contemporary art.

Today that collection represents a who’s who of modern art — works by David Hockey and Ray Lichtenstein on the Celebrity Century, an Anish Kapoor mirror on Silhouette, a Jim Dine heart sculpture on Solstice, a Robert Indiana iconic LOVE sculpture on Millennium.

Dale Chihuly, a renowned glass artist, created chandeliers for the Celebrity Constellation and Infinity — as well as for Disney Cruise Lines’ Disney Magic and Disney Wonder.

On the new Celebrity Reflection, currently doing its first season of Caribbean cruises out of Miami, guests heading to dinner will pass a Jeff Koons Mirror Flower in an aft stairwell.

Working with a $5 million budget, Capuzzo acquired 136 new works for Reflection. Also on display are 115 standout works from the cruise line’s collection — including from ships no longer in the fleet.

Represented on Reflection are Robert Rauschenberg, John Baldessari, Julian Opie, Kiki Smith and Richard Prince, with conversation pieces including Ann Veronica Janssen’s gilded gold Venetian blinds.

On all the Solstice-class ships Capuzzo worked with a curatorial theme — on the newest ship it is “The Seductiveness of a Reflection” — and in each case an artist was commissioned to create a standout container for a live tree in the Upper Grand Foyer. On Reflection, the commission went to Bert Rodriguez, who created a sculpture of extravagant metal branches reflecting the live tree on top.

In a coup, Celebrity recently showed off the art on Reflection to the art world hosting an onboard VIP event during Art Basel Miami Beach.

Conceptual artist Rodriguez even did a performance art piece called Everywhere I Look, I Only See Myself for the occasion. It involved him interacting with a body double.

The collecting continues. For the Riviera and Marina, Del Rio said putting together the collection took him a few years and he’s still buying. He recently made purchases for Regent’s Seven Seas Navigator. Several Miami artists are represented including Andre Allen, Russell Sharon, Susan Feliciano and Baruj Salinas as well Cuban artists Jose Agustin Grillo and Gay Garcia.

“The good news is I have no other hobbies,” Del Rio said with a laugh. “I have no academic credentials for putting together this collection, but it turned out pretty good, I think.”