Being an international business person in a land-locked city nearly 1,000 miles from the nearest international border might appear to be challenging at times. But of course so much business is 
conducted over a web portal, your international customer or business partner is typically no further than your computer terminal. In the end, however, nothing can compare with a face-to-face interaction, and almost no matter where you begin, to get to where you're going you will need to travel through an airport.
I am pleased to be able to do a little home town cheerleading here and point to an article in the current issue of Business 2.0 which profiles the 5 best international airports for travelers in the U.S. and trumpet the fact that Denver International Airport (DIA) is among them. The article notes that U.S. airports probably don't measure up to the best in foreign airports (an experience that I would attribute to the newness of some of the better airports in Asia and the seemingly inherent sense of design and function in architecture evident in many facilities in Europe), but in my own experience, DIA ranks not only among the best in the U.S., but among the best in the world. Another reason why no matter how invigorating a trip abroad may be, it's nice to arrive safely home.
While we're on the subject, share your comments on the best and worst international airports you've experienced. I'm going to give this some more thought, but as a first reaction I would say best is the new airport in Shanghai and the worst is Heathrow -- at least among airports in major cities.