One travel manager is spearheading the drive to formulate an "Environmental Code of Practice for Business Travel." Lynne Bicknell, management services manager for London-based Salomon Brothers International, says her committee of U.K. travel managers hopes to have a voluntary code written by next March.

The new code will be a checklist, according to Bicknell. Questions for hotels, for example, may address recycling programs, air-conditioning and water systems, and airport transportation for guests (so they don't have to take individual taxis). For airlines, questions may focus on aircraft age and aircraft emissions. A second part of the code will ask companies to evaluate their own (and employees') stance on environmental concerns.