Cruising aboard a luxury ship is the sort of rarefied travel experience most of us can only fantasize about. There are only a few cruise lines – the priciest afloat – where one finds caviar and bubbly served before dinner by a white-glove butler or very seasoned room steward. Men in black tie and women in elegant gowns dine in intimate restaurants on the finest food afloat, served by the most experienced crew in the world. And these ships cruise to the most exotic parts of the globe, with top lecturers aboard who are experts in the areas visited.

But no other segment of the industry seems to present more confusion about the choices of ships. While the five luxury cruise companies listed below all excel in high levels of food and service, large comfortable cabins and exotic itineraries, there are still enough significant differences in style, size and ports to warrant some further study.

If you’re new to luxury cruising, don’t be confused by the cruise lines calling all cabins “suites.” Technically, true suites have two separate rooms and are very rare in the cruise industry. Staterooms “suites” are simply larger balcony cabins. They are measured in square feet and I suggest that you use this as your standard when comparing cabins from one category to another and one vessel to another.

Since I think you need a very experienced travel agent to make sure your voyage is flawless, I recommend finding a top agent through Virtuoso and America’s Vacation Center, both with years of experience in booking luxury cruises.  Herein lies my take on the subtle- and not-so-subtle differences I’ve found when good fortune had me sailing with the luxury cruise lines.

Crystal Cruises

Crystal’s two 960-passenger ships, Crystal Symphony and Crystal Serenity,are — aside from the mammoth QM 2 – the largest luxury vessels afloat. While there are lovely alternative restaurants (with a small surcharge), this is a two-seating ship with assigned dining, a negative for many luxury cruisers. And pricing for these ships is far from all-inclusive, since the fare does not include gratuities or complimentary wine with any meals.  This is the dressiest cruise experience I’ve ever taken, with black tie and gowns the norm on formal nights; in fact, if you don’t want to conform to the suggested dress policy I suggest that you skip this ship.

Still, Crystal Cruises outshines the other players with on-board lectures, lessons and seminars. After dinner, the action continues with lavish Las Vegas-style reviews and the largest, busiest casinos in the luxury segment. You’ll find more days at sea and fewer ports of call on Crystal’s itineraries, a plus or minus depending on your preferences. The most popular accommodations are the Penthouse Suites, which all have butlers. Crystal is the only cruise company that gives solo cruisers a break: The single supplement is only 25 percent above the per person, double occupancy rate.

Fellow passengers:Crystal’s 65+ passengers love the full-day lineup of speakers, lecturers and lessons; at night, this is a glitzy bunch that stays up late frequenting the casino and shows. Bring gowns and tuxes for these elegant voyages. That’s why Crystal is my pick for solo cruisers – on board activities enable you to meet many new friends.

The Bottom Line:The cruise fare does not include alcohol, wine, gratuities or any special shore excursions. And pre-dinner caviar and champagne is extra as well. However, singles get the biggest break in the cruise industry with single supplements of 125%. Reality rates are closer to $300 per person, double occupancy during the 2009 recession.

Crystal Cruises’ biggest plus: It’s my pick for the warmest, most professional staff and crew, with the most consistently high levels of service. The food is also superb. The shore excursions are very pricey, but they are among the best offered by any cruise line in terms of diversity, attention to detail and comfort. Crystal offers more days at sea with non-stop lessons, guest lecturers and activities. The only cruise line offering low-cost single supplements.

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CUNARD LINE

While Cunard says it no longer operates three-class ships, it really does. If you purchase  Queen’s Grill accommodations aboard Queen Mary 2 or Queen Victoria, your cruise experience will be very luxurious indeed. Of course the staterooms in the top category are much bigger and you also have a terrific concierge lounge/service that is a big plus when making reservations or booking a taxi to meet you at the pier. But the big difference is dining in the single-seating restaurants created exclusively for passengers booking Queen’s Grill suites.    While I think the restaurant resembles a airport business class lounge on QM 2, it is are stunning aboard Queen Victoria.

In addition to more real estate, Queen’s Grill passengers have butlers who will pack and unpack your bags; a bottle of French champagne and early embarkation.   The single, open seating Queen’s Grill restaurant is a true gourmet experience and you may order whatever you please.

While Princess Grill suites also share the concierge lounge and have a separate dining room, I’m not including them in the luxury category.  When I sailed the food and service in Princess Grill was mediocre, perhaps because it does not have its own kitchen as the Queen’s Grill does.  In addition, you get a larger cabin but little else.

Important caveat: I only recommend Queen Mary 2 on transatlantic crossings or World Cruises.  Because she is one of the largest vessels afloat QM 2 can’t dock in most of the world’s ports requiring passengers to transfer between the ship and the port via large tenders (boats).  This is a very time consuming procedure that cuts down on the shore-side experience.

Fellow Passengers:Cunard markets Queen Victoria to English and other European cruisers.   Aside from her annual world cruise, the ship sticks to Mediterranean itineraries. My pick for one of the grandest, most elegant ship experience is taking Queen Mary 2 transatlantic between New York and Cherbourg. On crossings, you’ll find more sophisticated travelers and a mix of Europeans and Americans in a wide range of ages, 40+, and even families with young children.

Exclusive Features I Love: Queen Mary 2 boasts the largest library at sea, top-flight lecturers, ballroom dancing to a live 17-piece band and even a planetarium.

The Bottom Line: Not factoring in discounts, Queen’s Grill staterooms start around $560 per person, per day on six day transatlantic crossings.  The fare does not include gratuities or any alcohol consumed aboard ship.

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Regent Seven Seas Cruises

This cruise line’s three modern luxury ships include the 490-passenger Seven Seas Navigator; and the 700-passenger sister ships Seven Seas Mariner and Seven Seas Voyager. They attract a well-heeled but less pretentious traveler. Single, open seating dining translates into a more leisurely atmosphere. The larger Mariner and Voyager each boast a choice of four restaurants, including Compass Rose, another restaurant serving food prepared by chefs from Le Cordon Blue school of Paris and, new this year, all ships will boast steak houses. At night, everyone seems to disappear after dinner and head for a cozy lounge or their cabins, where videos and complimentary CDs are popular. Unlike Crystal, fares include gratuities, all beverages, including spirits in your stateroom when you arrive. One superb service offered by Regent is a “Travel Concierge” who can arrange independent sightseeing, entrance to closed art exhibits and anything your heart desires. This is the only cruise line using a top-flight company, Carita of Paris, to operate the ship’s spa.

With seven-night Europe itineraries, Regent is attracting a younger affluent crowd to luxury cruising. These are port-intensive itineraries and passengers are early to rise and early to bed. If you’re new to luxury cruising and don’t want to haul a mountain of gowns and shoes on your cruise, this may be your cup of tea.

Fellow Passengers: Couples in their 40s and 50s are more prevalent on Regent Seven Seas (formerly Radisson Seven Seas) Europe cruises than on the other luxury vessels. On itineraries over seven days, passengers are normally 65+.

The bottom line: Upon arrival, you’ll find your favorite spirits already stocked in the cabin. Fares, which start around $400 per person, per day, include wine with lunch and dinner, plus gratuities.

Exclusive Features I Love:Regent Seven Seas Cruises biggest plus: the new “travel concierge” aboard each ship, who will book any shore activity you like or book individual sightseeing excursions, making it easy to tour with private car and driver and visit attractions most tourists miss. This cruise line also offers the best spas afloat, operated by the famous Carita of Paris, as well as Cordon Bleu dining and a choice of four restaurants. Regent recently launched an innovative “Circles of Interest” program on Europe itineraries featuring three special topics per voyage, such as art and design, architecture and cuisine, so passengers can delve more deeply into their specific interests. Each “Circle of Interest” theme includes lectures aboard the ship and excursions ashore led by the expert in that field. Not only is your experience ashore enhanced but passengers and lecturers in each small group bond more closely.

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YACHTS OF SEABOURN

The line’s three tiny ships — Seabourn Pride, Legend and Spirit- are 208-passenger, yacht-like vessels offering the best itineraries afloat, navigating into fabulous tiny ports larger vessels could never visit. Built in the late l980s, these ships lack balconies, but some cabins have “French windows” that allow the sounds of the sea to enter your stateroom. Entertainment and nightlife are limited, but you’ll dine on some of the best cuisine at sea, served by an impeccable crew, many of whom have been with the company for years. Service is a critical aspect of luxury cruising, and some of the best is found on Seabourn, which has the largest number of staff per passengers. By the end of a cruise everyone will have been invited to dine with senior officers and often the ship’s Captain. On Seabourn, everyone gets dressed to the nines a few nights during each cruise. However, a day at sea may seem endless if you’re active or restless since there is little to do and very limited public space. One Seabourn executive described the main on-board activity as “conversation.”

NEW VESSEL TO ENTER FLEET:Seabourn is introducing a brand new ship June 24, 2009, the 450-passenger Seabourn Odyssey. She will be loaded with large staterooms, 90% with private verandahs and there will be four restaurants to choose from.

Fellow Passengers: Sophisticated, dressy and primarily 60+.

The Bottom Line:Fare includes all alcoholic beverages and gratuities. Fares run as high as $800 per person, per day outside recessions. At present, Seabourn is offering discounts of 50%+

Seabourn’s biggest plus:The best itineraries on earth, very personal service and haute cuisine. In major shopping ports, Seabourn offers the services of a personal shopper with car and driver. And you’ll find one exclusive shore excursion on each cruise — like caviar and champagne served by waiters as you lull in a secluded Caribbean cove.

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Silversea Cruises

The 296-passenger Silver Cloud and Silver Wind or the slightly larger Silver Shadow and Silver Whisper (382 passengers) cater to a dressy and very chic international crowd of “been there, done that” travelers.

Silversea gets my vote for the most beautiful ships in the luxury category, and offers my favorite suites in the cruise industry, the Silver Suites, found aboard both sizes of ships. These are beautiful vessels with more than enough public rooms, plus a good spa and fitness center, to keep passengers busy during days at sea. There is one main dining room plus the ship’s cafeteria, which is set up for theme alternative dining at night. This cruise line has one big problem, inconsistency. I have experienced inconsistency in food and service on Silversea – one voyage was as close to perfection as it gets, but a year later I found spotty service and so-so cuisine, and this was on the same ship! Still, it’s safe to say you’ll find glamour, good service and beautiful, spacious ships with all the creature comforts one expects today. A new, comprehensive “Wellness Program” helps you create a fitness regimen and dine on low-fat, low-carb gourmet cuisine.

Fellow Passengers: Wealthy passengers from many countries, the majority in the 65+ age group, although I’ve seen families during summer months and holidays. You’ll frequently find a mix of American and European passengers who enjoy getting very dressy at night.

The Bottom Line:Practically everything is included in the cruise price, like mixed drinks, wine and gratuities. Per person, per diem fares can be as high as $800 per person, per day but during the 2009 recession you’ll find very steep discounts.

Silversea’s Biggest Plus: Beautiful ships and lovely cabins, top flight itineraries and gracious service.