In the race for supremacy among travel search engines, there is one obstacle that none of the companies have been able to overcome.
''When you get into a display with other carriers, there's really no opportunity to display all the options available to the consumer," said Jill Howard-Allen, manager of interactive marketing at Southwest.
Without Southwest's participation, none of the emerging travel search engines, including Sidestep, Kayak, Mobissimo, and
Southwest's absence is also a hindrance for consumers looking for a quick and effective way to search the air fare universe. It means they have to keep searching multiple websites to find the best deal; currently, most consumers check three to four websites before purchasing an airline ticket.
Sidestep has the closest relationship with Southwest. It carried the airline's fares on its browser search tool until the airline decided to pull them off in January. It now offers only a link to the Southwest website when a user hunts for a fare on a route served by the airline.
''They're still trying to figure out this travel search category as a whole, and wanted to treat people relatively equally and spend some time thinking about travel search before they dive in," said Phil Carpenter, a spokesman for Sidestep.
Kayak, one of the most aggressive travel search engines, is clearly frustrated by its inability to incorporate Southwest into its searches.
''Our goal is to be completely comprehensive. Our goal is to have everything," said Paul English, cofounder and chief technical officer at Kayak.
English said Southwest eventually will have to reconsider its position, as search engines snare more and more Internet travel traffic. He says Southwest is no longer always the lowest-cost option and, as a result, the airline doesn't like being compared side-by-side with other carriers.
Southwest officials say their reluctance to participate with the travel search engines is not because they fear competition.
''It's not a function of not wanting to be compared with our competitors," said Whitney Eichinger, a Southwest spokeswoman. ''We want to keep our customers coming to Southwest.com."
The Southwest officials say other websites are not capable of presenting all of Southwest's flying options to consumers in a fair and coherent way. Southwest also is determined not to relinquish control of its customers to third parties.