Airlines could soon start offering customized fares to travelers based on how regularly they fly, where they live and the kind of trip they are taking.

The world’s largest airlines have agreed to adopt a new standard for distributing airfare information that could significantly compromise the privacy of customers and allow carriers to charge travelers different prices for the same trip. Many airlines have struggled with high fuel costs and aggressive competition from low-fare carriers. They may be counting on the new airfare pricing standard to increase revenue and profits. It is hard to see how this approach could result in more competition or anything but higher costs for many travelers.