Just as every traveler has a unique style, set of interests and vacation needs, every luxury cruise line has a personality unique to its brand. Some lines will emphasize certain aspects of the cruise experience over another -- like the level of all-inclusivity, food and wine, spa facilities and destination immersion. You need to ferret out these subtle differences in order to find your best match and the ship of your dreams.

Personalized service is the hallmark of a luxury voyage. You will feel like a VIP on all luxury cruise ships, which have a shared goal of exceeding your expectations and anticipating your needs. On larger ships, service might be a bit more formal and reserved. Your suite butler will see to it that everything you need -- from breakfast in bed to afternoon canapes or an evening nightcap -- is executed flawlessly.

On yachts and intimate riverboats, the service might be delivered in a more personal way. You will be addressed by name throughout the ship (even on embarkation day). Bartenders will learn your drink of choice. Waiters and waitresses will recommend options in the dining room based on your previous selections.

Many of the traditional luxury cruise ships share a similar profile: high space-to-guest ratios throughout the ship; and large cabins (which are usually referred to as suites) that include balconies, spacious marble bathrooms outfitted with both a full-size tub (often a whirlpool) and separate shower (often with rain showerhead), with an array of high-end bath amenities from purveyors like L'Occitane, Aveda, Hermes, Molton Brown or Ferragamo.

Linens in suites and in the dining rooms will be from top designers, as will the china, silverware and glassware. (For example, that Champagne toast at dinner will likely be poured into Riedel, Baccarat or Schott Zwiesel barware.)

Luxury riverboats, on the other hand, will lack the spacious cabins found on its oceangoing counterparts but will still offer things like high-end bath products in your cabin and designer china in the dining room.