Abstract: A method and airline booking system for converting fare rules into computer code for efficient fare validation and/or for calculation of sundry costs is disclosed. In one embodiment, the method includes converting fare rules into computer code and storing the computer code. The method also includes receiving flight criteria from a user and identifying candidate fares satisfying the flight criteria received from the user. The method further includes retrieving and executing the computer code to determine which of the candidate fares satisfy the fare rules embodied by the computer code.