Look for travel agents that are members of CLIA and have ACC and MCC credentials
The prevailing wisdom is that booking a cruise online will get the lowest prices, but also that it's a very impersonal experience. The corollary to this accepted truth is that finding and using a cruise travel agent to book a cruise will get you highly personalized service but generate a higher price for doing so. Are both statements correct? What's the better way to book a cruise?
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Let's start off by recognizing that, for the most part, a cruise is not a commodity product. It's not like buying a toaster, where you often know the specific make and model you want to buy. If you do know the name of the cruise line and ship you want, and you even know your preferred cabin number and sailing date, then by all means, search every method you can to find the lowest possible price you can for that cruise. If this means booking via an electronic method, booking directly with the cruise line (most cruise lines today will take a direct booking; whether they give the lowest price for that booking is a different story), or finding a travel agent with a lower price, go for the lowest price. As long as you know what you want, buy it at the cheapest price you can.
But, as I said, this not usually the case. In most cases, the prospective cruiser isn't going to know all of those factors. Let's go to the other end of the spectrum. Let's take a first-time cruiser who has no specific idea of the line, the ship, the deck, the stateroom, the season, etc., not to mention the other issues to deal with: first or second seating (or fixed or varied seating), port or starboard, air/sea or cruise only, insurance, etc. This cruiser needs hands-on help to make all the right decisions.
To start, this cruiser should find friends and family who have cruised and get as much advice as possible. Once they have separated reality from fantasy in those personal experiences, they can approach travel agents who are in the best position to provide further help. Can on-line booking services (e.g., Travelocity, Expedia, Orbitz) do this? No. They can provide facts and figures. But they cannot provide the travel agent's professional experience, nor can they answer questions back and forth.
Of course, CruiseMates can really help with all the information on this website generated by experts -- but this isn't a booking service. That distinction is critically important. Don't expect to get truly subjective advice from an online booking service. Unless you get through to a human agent or supervisor, the machine will not provide the kind of extensive information you'll need. It's there to make the booking. When it comes to helping you understand why it may be better to have early sitting for dinner in Alaska but late sitting in the Caribbean, you need someone who knows what they are talking about.
CruiseMates can help, but that's where travel agents really shine, especially experienced travel agents. For the best assistance, look for travel agents that are members of CLIA (Cruise Lines International Association) and have gone on to get their ACC and MCC credentials (sort of like higher education degrees in cruise knowledge). Travel agents will do comparison-shopping for you among different lines and ships and decks and dates and work to get you the best deal on the best dates.
Do these travel agents have rates as low as some of the huge electronic services? I'd love to say yes. I'd also love to be able to tell you that every travel agent knows everything there is to know about every detail. They don't. But on a sliding scale, the more questions you have about a cruise booking, the more likely you are to need a travel agent. And the reasonably small difference in cruise fare you might pay for using the travel agent is really worth the money in the long run. First of all, you can keep calling them with any question that comes up before your sailing date. If something goes wrong during your cruise, they will help you resolve it once you get home. And if a world crisis is brewing (sound familiar?) while you are booked, they are in a position to know what's going on and can advise you about the cruise line's cancellation policy. Also, let's be fair. If you do use a travel agent to do all of your comparison-shopping and to answer your questions, don't go on line and book the same cruise just to save $50 or so. That just "ain't cricket" as they say. Reward the travel agent with the booking.
Bottom line: Which of those initial "prevailing wisdom" statements is correct? Neither is 100% correct or incorrect. Travel agents and online booking services both have their place in the cruise universe. The right one for a specific cruiser depends on the needs of that cruiser. If you have lots of questions you need answered, use a professional travel agent. If you don't have time to do all of the comparison-shopping yourself, use a travel agent. If you know precisely what you want and are comfortable using a computer, and do not need personal attention, try an electronic service.