The FLSA clearly defines what exempt employees are. They're generally either fully salaried management or they're commissioned outside sales personnel. Here's a link to a web page with some good information from a New York law firm. http://www.flsa.com/coverage.html
If you're the employer and you're not understanding FLSA, you're getting yourself into some deep problems. This is a mature federal law and there's a wealth of information out there to explain it in detail. The Illinois Department of Labor has much on its own website. Intentional (or possibly even accidental) violations of FLSA can ruin small businesses.
I hope this helps. If not, I'd suggest you speak to a live lawyer about the issues you raise.
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