Business travel is growing within the U.S. and across the globe, especially with the booming economies in China, Brazil and Australia.

But an innocent hand gesture can doom what otherwise would be a very profitable trip across international borders.

International business trips, launched from the U.S., reached 6.78 million trips in 2011, a 3% increase over 2010, according to the Global Business Travel Assn., a Virginia-based trade group.