1. Never reveal a candidate's name or contact information -- verbally or on a resume -- unless you have a written referral agreement with your client company.

2. Make sure your signed referral agreement gives you credit for referred candidates for a period of at least a year, and that your ID on the candidate extends to the company's various divisions and departments.

3. Never disclose your client company's name to a candidate until there's a mutual level of interest sufficient to arrange an interview.

4. Utilize verbal firewall strategies to protect the identity of your candidates and clients. For example, if the company asks for the candidate's name, you can say, "I've been asked to keep the person's name confidential." If they ask, "This wouldn't be John Smith, would it?" you can play dumb and say, "John Smith? Who's he?" Or, if the candidate wants to know the name of your client company, you can simply describe the company, in terms of its size or general characteristics.

5. always use the "you go first" technique when playing the identity game. If the hiring manager says, "I think I know who your candidate is," you can respond, "Really, who is it?" rather than offering to reveal his name.

There are exceptions to the disclosure game, of course. If a candidate has been actively interviewing, it makes no sense to cause confusion or duplication of efforts if the person has already interviewed with your client company. But by in large, the best way to protect your inventory -- and your income -- is to play it close to vest.

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