"We will have submarines," announces Edie Rodriguez, president of Crystal Cruises, in a tone of voice that’s disarmingly forthright. It’s a surprising statement: the concept of allowing customers to see below the ocean and just a few feet above it sounds like an unorthodox move for any cruise industry operator.

Yet, amid a huge spending spree by operators in the luxury sector, inhibitions – inspired by minimum guest-to-space ratios and routine destinations – are rapidly disappearing. Recent years have seen operators refine their offerings into everything from cruises to the polar ice caps and intimate meals curated by Michelin-starred chefs, to historical tours made possible through partnerships with UN agencies. In short, it doesn’t really matter whether the sky’s the limit or if it’s the seafloor, as long as guests know either option is available.

The high life

If anyone embodies this new expansionary attitude, it is Edie Rodriguez, currently at the pinnacle of a career in the travel industry spanning 34 years. Her appointment in 2013 instantly saw her argue that the long-term viability of Crystal lay in aggressive expansion within a market growing by the day. It certainly persuaded the operator’s parent company Genting into action, which promptly backed Rodriguez’s ambitious acquisitions programme that included three 1,000-passenger ships, two riverboats, a luxury yacht and a custom-fitted Boeing 747.

It is an investment predicated on the assumption that netting new customers to fill these vessels will not be achieved by widening Crystal’s demographic appeal, but by doubling down on what they already offer. "Today’s 50 is the new 30," says Rodriguez. "Age is only a number. It’s a mindset." Hence the operator’s investment in submarines, kayaks and Zodiacs: vehicles that Crystal’s president asserts have as much appeal for baby boomers as they do for customers half their age.

The first vessels taking this assumption on board will be Crystal’s new Polar class of passenger liners. "They will have marinas like our yachts, so passengers can go down in the submarine we will have on board," says Rodriguez. "We’ll also have a landing pad and a helicopter, to conduct shore excursions and basic transfers of crew and passengers."

Underpinning this is a faith that the experiences currently on offer at Crystal already encourage lasting growth.

"Many families consider it their wider passage to do a family reunion with us, and now, as their children have grown up with Crystal, they are coming back," says Rodriguez. "At Crystal, we have quite a legacy."

"We sold out in three days for a departure two years away, and we have 713 guests on the waiting list."

Similar priorities are on show at Seabourn. "As a brand, we focus on two groups," says Rick Meadows, the company’s CEO. "The first is a 65+ demographic. They’re a little older, well-educated and very travel-savvy. We also have another market that we really focus on – I would call them more the ‘working wealthy’ – and they’re between the ages of 45-64."

Like Crystal, Seabourn is embarking on a concerted shipbuilding programme. Next year, Seabourn Encore will be released from dry dock, to be followed in 2018 by the Ovation, the Sojourn and the Quest. However, where Crystal has prioritised technology, Seabourn has chosen to emphasise the roles of design and culinary experiences in augmenting their offering to customers.

"We’re always thinking about how we can connect even more with our guests and, quite frankly, think about what their expectations would be and then exceed them," says Meadows. It was to this end that Seabourn chose to enlist Adam Tihany – an interior designer best known for producing Michelin-star restaurants – to design its new fleet. Among other features adding to the VIP feel, new menu items have been introduced, curated by renowned chef Thomas Keller.

The Northwest Passage

As their fleets expand, Crystal and Seabourn are seizing the opportunity to have their vessels travel to destinations off the beaten track, in a hunt for landscapes and experiences previously inaccessible to the cruise market. Most strikingly, this has manifested as more trips to the most extreme places cruise ships can visit. "We started voyages to Antarctica a few years ago, and we now have a very successful operation there," says Meadows. "We provide the opportunity for our guests to disembark on a Zodiac and do landings each day they’re there."

At the opposite pole, ice sheets have receded enough for Crystal to safely deploy ships to the Arctic Ocean for the first time. "We opened in August 2014 with a 32-night voyage two years hence, from Anchorage to New York via the Northwest Passage," declares Rodriguez. "We sold out in three days for a departure two years away, and we have 713 guests on the waiting list."

Luxury cruise operators are also responding to a desire among consumers for a more nuanced and sustainable approach to the onshore excursion. The small two-ship line Paul Gauguin Cruises perhaps leads in this race, having attained the participation of oceanographer Jean-Michel Cousteau on the operator’s voyage around the Society Islands in April. French line Ponant have also announced their desire to "develop enrichment programmes with a focus on cultural voyages and expeditions to all seven continents".

It’s certainly a pattern to which Seabourn has paid special attention. In June 2014, the operator announced the extension of a partnership with UNESCO that allowed guests privileged access to World Heritage Sites and, by charging premium rates, contribute to their preservation. Meadows adds: "On a number of these tours, we have speakers join us for something we call our Seabourn Conversations Programme, which brings local culture and insight together to develop a much more interesting and relevant point of view."

"We have one complementary shore excursion for our guests and crew per itinerary, where we go to give back to the community that we visit."

Meanwhile, Crystal has begun to incorporate philanthropy into a number of its shore excursion offerings.

"We’ve found that our passengers are becoming more charitable," says Rodriguez. "Therefore, we have one complementary shore excursion for our guests and crew per itinerary, where we go to give back to the community that we visit. It might be working with senior citizens in one area, or it might be bringing blankets to a children’s hospital."

A race for space

Passengers on Crystal and Seabourn new vessels are also benefitting from the increasing priority placed on maximising the size of cabins. "While our ships today comfortably host 1,000 guests, our newbuilds will be slightly larger to offer greater guest-to-space ratios," says Rodriguez. Naturally, this has opened up new options for luxury operators in the realm of interior design. The Tihany-designed Seabourn Encore, for example, will boast 300 suites, each with their own verandas and marble-floored bathrooms.

Crystal, meanwhile, has opted to take the idea of the passenger cabin to its logical endpoint, offering permanent residences on its future vessels. "We will offer up to 48 apartments of 600-4,000ft² for a lucky few," says Rodriguez. "And compare that with, let’s say, the branded luxury property at the Baccarat Hotel in New York. It’s a hotel, but it also sells condominiums for $20-50 million. Guests will be able to go up in their own elevator and have all the privacy they want."

This isn’t a new development within the cruise sector, with the concept first put to the test on The World, launched in 2001 as the first residential cruise liner. Another such ship, the South Korean-built vessel Utopia, is scheduled to set sail in 2016. The concept of the permanent voyage may well become a new trend in itself, but for the moment, Crystal and Seabourn remain optimistic.

"Crystal society members are loyal, and the people who want to be new to Crystal are very bullish when we launch new destination experiences," says Rodriguez, and the same seems true for Seabourn. "There’s a tremendous amount of innovation and new thinking, particularly as it relates to the luxury category," says Meadows. "I think it’s a very exciting time for the industry."