If you plan to cruise even just one more time in the future, a cruise club is guaranteed to help you save at least a few bucks. If you intend to cruise year after year all over the world, you'll be throwing away hundreds or perhaps thousands of dollars if you don't join. The clubs just plain make sense.

Almost every major cruise line has a frequent travelers’ club, sometimes called a loyalty program, with the goal of getting you not only to book again, but to book again aboard the same fleet of ships. They want to offer you as many perks as it takes to keep you coming back to their ships instead of giving your hard-earned vacation dollars to a competing company.

Royal Caribbean, for instance, calls its loyalty program the Crown and Anchor Society. It has several levels of membership, ranging from Gold (you're eligible after your first cruise) to Diamond Plus (you're eligible after you have completed twenty-four cruises, or twelve cruises with a suite booking). You get added benefits during your cruise, such as complimentary wine tastings, private departure lounges, priority wait listing for sold-out shore excursions and spa appointments, and preferred dining-room seating. You also get benefits in between cruises, such as savings certificates within the Crown and Anchor magazine, members-only contests, and special offers on rates for balcony and suite staterooms.

Princess Cruises has a similar program, called the Princess Captain's Circle. It has three levels ranging from gold (you're eligible after your first cruise) to elite (you're eligible after your fifteenth cruise). As a member of the Captain's Circle, you automatically become part of the Referral Rewards Program, which lets you refer your friends to Princess via the company's Web site. If your friends book their first Princess cruise, they get a discount. After they complete their trip, you get the same discount offered to you. Other Captain's Circle benefits include upgraded cabin assignments aboard and priority room assignments ashore, free upgrades to higher levels of travel insurance, complimentary dry cleaning and laundry services, and discounts at the ships’ boutiques.

Sometimes, a cruise company's loyalty program will not help you financially on every future cruise, but will help you substantially with select itineraries. The Silversea Venetian Society is a good example of this concept. If you become a member, you can in some cases get as much as a 10-percent discount in addition to early-booking savings and advance payment bonuses. However, the discounts only apply to certain cruises. Check with the company before joining the loyalty program to see if the next cruise you have in mind might qualify for the added discount. In some cases, you might find a better deal with another cruise-line company.

Carnival Corporation, the parent company of Carnival Cruise Lines, takes the customer loyalty idea a step further with its Vacation Interchange Privileges program. If you cruise aboard a Carnival Corporation ship, you will be entitled to the “past guest” savings offered aboard every other cruise ship company under the same corporate umbrella. The cruise lines that participate, in addition to Carnival Cruise Lines, include Costa, Cunard, Holland America, Princess, Seabourn, and Windstar.

If your cruise company of choice wasn't mentioned in the preceding paragraphs, don't worry—odds are good that it has a loyalty program similar to one of the others described here. Ask your travel agent for details, or check the fine print in the back of your brochure.