While 2008 saw booming business for event professionals involved with mega events such as the Summer Olympics and the U.S. presidential campaign, the year closed with crashing markets and crunched credit lines.

No surprise, then, that the median change in revenue from 2008 to 2009 that our big players predict is a 10 percent decline.

But as you can read below, the experiences of individual companies vary widely, with some scrambling to make up losses of close to 70 percent by picking up social business while others expect an even stronger year in 2009.

A notable aspect of this year's list is that while revenue will be down, the falloff in number of events shows a median decline of only 1 percent. It appears that event companies are staying busy--and in business--with smaller events.

Note: This list appears free for Special Events subscribers and is available online for a nominal fee. For ordering information, please click here.