When a staff member approaches you with a specific complaint about a peer and asks that you keep the comments secret, beware the situation that could develop. When anonymity is requested, it's best for managers to be on the defensive.

Every manager has been there: An employee comes into your office and asks if he can talk to you for a minute. After closing your door, the employee launches into a 30-minute tirade about how another team member is driving him crazy by coming in late, missing deadlines, snapping at the most innocent questions or criticismsâ€"you name it, you've heard it.

You sit there, nodding patiently, and at the close of the employee's venting session, you say that you'll look into his complaints and see what you can do to resolve the situation. And then, as the team member prepares to leave your office, he plants this little managerial land mine: "You won't tell Joe that I came and talked to you, right?"

Red flags everywhere
I cringe to recall how many times I've been hit with that one, and recoil even more violently at the number of times I've screwed up when faced with this deceptively treacherous predicament. When I was much younger, I actually snapped at an employee and said something to the effect of: "No, I won't talk to Joe. I'll just assume that everything you said is accurate and run off to fire Joe right now without ever giving him the right to face his accuser."

I still want to say that every time I'm confronted with this situation, but common sense and human resources regulations have tempered my response over the years. Still, employees' tendency to look at managers as the workaround of every dispute is a huge irritation. I've come to believe that the ability to engage in constructive conflictâ€"either instinctively or as a learned behaviourâ€"is perhaps the great divide between managers and many of their employees. Very few people like confrontations, and many folks are absolutely terrified of them, even with you as a buffer.

You have to be receptive to your team member's concerns. But the great risk of listening to an employee's "confidential" rant is that you'll end up the bad guy from everybody's perspective. Obviously, you're going to have to do something about a complaint, even if it's just finding out enough about the situation to decide that it's really no big deal. As a manager, you make bigger waves than you think. Everyone on the team will know that you're snooping around, and you can bank on the fact that many of them already know that a "confidential" complaint has been filed. The team member who is the brunt of the gripe will have a good idea of who came to you with a grievanceâ€"people just instinctively know that kind of stuffâ€"and as a result, the confidential complainer will assume that you've ratted him out.

It's really a no-win situation.

The worst-case scenario is that after you've gone through a few hoops and actually found a problem at the root of the confidential grievance, complaining employees wimp out in the face of conflict and claim that they never really had a beef in the first place. I've seen it happen several times, in situations that range from gripes about the performance of a socially popular employee (at least in some circles) to serious allegations of sexually harassing behavior. This complication most often arises in cases where employees have complaints about other managers; any such issues should launch a huge red flag as you evaluate the best way to proceed.

The manager's best defense
I often wrap up my columns with a list of tips, but I'll call the following bits of advice "warnings"â€"I've come to subscribe to all of these approaches after some tough experiences. They are basically defense mechanisms, but they can get you on a solid footing as you begin to tackle an employee's desire to talk to you "off the record."

Make it clear up front that you can't guarantee anonymity
Employees need to understand from the opening of any "confidential" conversation that, as a manager, you may need to take action on what they tell you, and that may mean that their anonymity will be compromised. Of course, common sense sets the standard here; there's obviously no need to start a confrontation between your team members over a random comment overheard in the hallway. But if a complaint raises serious questions about professional ethics or potential liability to the company, it's your job to act, and that may mean disclosing your sources.

This may seem obvious from where you are sitting, but employees often assume a blanket of unquestioned anonymity when they speak to you "off the record."

If employees tell you that they simply can't talk to you about a problem unless they are guaranteed absolute anonymity, then it's time to loop in HR. Those formal channels, as distasteful as they may be, offer the most protection of a source's identity.

Reschedule for tomorrow and give yourself a chance to breathe
"Off the record" complaints often include little bombshells that you just aren't ready to handle on the spur of the moment. And employees always seem to want to have such conversations at the end of the day, after they've worked up the nerveâ€"and you're exhausted from the other 10 fires you've had to stamp out that day. When an employee expresses a need to talk to you about a confidential matter, ask the employee if it's absolutely critical that you speak right at that moment. If the answer is no, ask the employee to reschedule for early the following day, when you'll have a clear plate and can give all concerns your full attention.

Don't assume you're talking to just one person
"Anonymous" complaints rarely are truly anonymous. You can safely bet that team members have griped to their peers about a situation before they come to you to talk about it. There's nothing you can do about thisâ€"it's just human nature. Just be aware that "off the record" conversations are most likely evidence of a deeper problem on the team than just the details of the complaints you hear behind closed doors.

Don't rush to get the conflicting parties together
When an employee complains about a peer, my first instinct is to tell the employee to talk to the peer about the problem and work it out. I still believe that this is often the best approach, but you need to at least second-guess yourself for a few moments before issuing such edicts. I can't overemphasise how bad many people are at handling even the most minor conflicts, so a chaperoned session may be the best approach, particularly if someone is irked enough to come to you in private.

Take notes
If employees are concerned enough about a situation that they feel the need to speak to you privately, the least you can do is take notes about their concerns. This will illustrate how seriously you are approaching the situation and make it a lot easier to escalate the situation to HR or another manager if the situation calls for it.

Hone in on stuff you can measure
In evaluating any employee complaint, you should try to segregate items that you can measureâ€"missed deadlines, faulty code, poor attendanceâ€"and more ephemeral issues, such as attitude and interpersonal conflicts. With measurable items, there's seldom any problem maintaining a whistle-blower's anonymity; you can just review a few records or logs and evaluate the situation from a fairly objective perspective without bringing anybody's name into it. If you're not already measuring the problem metric, start doing so immediately. You and the company get to be the heavy in this scenario, without falling back on a lame cop-out like, "I've heard that you've missed your last four deadlines, and your teammates are very upset."

If you need to escalate, do it in a hurry
Depending on how optimistic you are about human nature, you may think that you can just have a few chats with the involved parties and iron out any misunderstandings. In most cases, that's the right approach; but if a team member complains to you about serious misconduct by another employeeâ€"particularly if that employee is a managerâ€"get your boss or HR involved immediately. Dabbling in such situations is just going to make you look like a conspirator in the eyes of both sides, and it increases the chance that the complaining employee will lose his or her nerve over time and back out on you when the going gets tough.

If this last piece of advice sounds a little cynical, so be it. It's just best to recognise the risks, both to the company and yourself, when dealing with employees who are upset enough about a situation to want to talk to you about it behind closed doors.

Copyright © 2009 CBS Interactive, a CBS Company. All Rights Reserved.
ZDNET is a registered service mark of CBS Interactive. ZDNET Logo is a service mark of CBS Interactive.