The earlier you can book a cruise, the better. I like Carnival's "Early Saver" option, and wish all cruise lines had that option. If there is a price drop up to 90 days before departure, see if the cruise line will make an adjustment (either in the form of a rebate or on-board credit). If it's less than 90 days before departure, the best you can hope for is an on-board credit. As you probably know, if you're trying to save money and are flexible with when you can sail, you can get some really good rates during "Off Peak" periods. We once booked a Western Caribbean cruise for late Sept. at a really good rate, knowing that it was during hurricane season. Because of rough weather (10ft. waves), our stop at Grand Cayman was cancelled, so we had an extra day at sea. A really good travel agent will work to get you the best deal possible, but you should stay in touch with him/her to see if there have been any price drops.