Clara Bosonetto Maerz, a retired travel consultant, offers her best tips for securing the best deals:

It's very difficult to get these deals. You have to be extremely flexible on travel dates — and a little luck doesn't hurt. The airlines advertise the deals very much like a car dealer might advertise a Mercedes for $20,000 and only have one to sell at that price; similarly, the airlines might be selling fewer than 20 seats a day at the sale price, and when those 20 seats are sold, the price goes up. You have a much better chance of getting the deal if many airlines are participating in the sale. When it's only one airline, you have to see the deal before 10,000 other people see it. Here's some information on how to search for the deals effectively:

• Travelocity.com: Enter your city pairs on the Home page of Travelocity.com, but don't enter specific dates. Click at the 'Flexible dates' button. The next page displayed will show the lowest round-trip price first and the participating airline. Make your selection from that list to view monthly calendars with dates highlighted where the special is available. You can continue to click through on Travelocity.com to make a ticket purchase, or leave the site and book the specific available flights at the specific airline.

• Orbitz.com: Orbitz.com also has a 'Flexible dates' option button at their Home page. The following "Flex Search" page gives you three options that test your flexibility. Choose from immediate travel options to find the best deal during a 30-day period. Again, click through to make your purchase or go directly to the participating airline's Web site.

• Itasoftware.com: Itasoftware.com is more difficult to use, but it can become an invaluable travel tool once you become familiar with its many features. It's a Web site that displays airfares for just about any domestic city pair, including international segments. Click at the "Looking for Airfares?" button. The next page has many options — from round-trip; one-way or multi-segment searches to fare searches for specific dates; weekend search or month-long Search. (Just above the main Search button you will see BOS in the sales city box. Always ignore it and click Search for results.) This Web site does not allow you to click through for purchases. When you find an airfare you want to purchase, copy the details and purchase at your favorite travel Web site.

• International deals: When searching for international deals, Kayak.com and Mobissimo.com are two more good options.

Remember that airline sale prices are not offered on every daily flight or during every season. Should you find an advertised special, or one of Clara's deals for the dates you desire, consider yourself fortunate. Also, keep in mind that government fees, taxes and fuel surcharges ($50 each way to the Caribbean; $65 each way trans-Atlantic; $75 trans-Pacific) are in addition to advertised airfares. If you're traveling internationally, these 'extras' could add as much as $280 to a sale rate.