Ask what you'll get if the cruise fare drops after you pay.
The best travel agents have the clout to make most cruise lines refund the difference in price. If a cruise line or travel agent does not guarantee price protection, ask if they will make you whole in some other way—say, through an onboard credit equal to the price differential. (Onboard credit is good for any expenses on the ship: your laundry, bar bill, Internet access, cruise line-arranged shore excursions, etc.) If the cruise line promises a free upgrade instead, make sure it's an upgrade in the amount of the price difference. Some upgrades are meaningful—say, if you're moving from a stateroom to a balconied suite—but some aren't—say, if you're merely moving from Deck 8 to Deck 9.

Protect yourself against the cruise line—or travel agency—going under.
Some companies may not make it through this bad economy. Protect yourself by paying with a credit card, of course, and by buying your cruise insurance not from the cruise line but from a third-party provider that will cover you if the line goes bankrupt. Sometimes, for older travelers with pre-existing medical conditions, it's far more economical to buy the cruise line's insurance. For those in their sixties and younger, however, TravelGuard offers an affordable policy that covers pre-existing illness if you buy the plan within 15 days of your initial cruise deposit, and that covers default of the cruise line (as long as it isn't on TravelGuard's list of financially unstable suppliers). Keep in mind that several large cruise-discounting agencies have gone belly-up recently. Never book through an agency that suggests you pay in full before the cruise line's deadline. "We've heard how one large agency is urging clients to pay in full now in order to get a bigger discount," warns Cruise Week editor-in-chief Michael Driscoll. "That's a sign of cash flow problems."

After you book, check the cruise line's Web site frequently to see if the price has dropped.
Most lines are lowering prices so often that travel agents can't keep up with all the changes. If you see the price fall, request the refund, upgrade, credit, or whatever was promised when you booked. I just got back from a Mediterranean cruise on the Norwegian Jade—for $75 per person per day. After I booked, I checked the Web site weekly and, over the course of several weeks, watched the price drop by $1,000. The cruise line's policy is that it will give only an upgrade or a credit if the price drops after you book. Nonetheless, the travel agent I used—Linda Allen of Brownell Travel, whom I chose specifically because Brownell is a top producer for Norwegian Cruise Line—wrote a letter to the line and got me a $1,000 refund. There is no way I could have received this refund on my own.