Q: One of our co-workers acts as if he could snap at any moment. "Barry" frequently talks to himself, sometimes asking questions and then answering them. He gives orders to others as if he's still in the military. When people talk about certain subjects, he becomes quite agitated.

Several of us shared our concerns about Barry with human resources, but so far nothing has been done. Since I don't feel safe around this person, I have considered looking for another job. Do you have any thoughts about this?

A: Predicting whether someone may become violent is difficult, even for clinically trained therapists. Some unusual people are dangerous, while others are simply odd. However, the fact that Barry makes you uneasy suggests that you should be careful around him.

When interacting with Barry, don't do anything to antagonize him. Remain pleasant and friendly, but avoid lengthy discussions, especially about topics which seem to upset him. If he begins to talk about conspiracies, weapons, or people who have done him wrong, those could be significant warning signs.

Since you and your colleagues continue to feel threatened, arrange another meeting with the HR manager or security department. They may wish to consult an outside expert who can help evaluate the situation. But if you truly fear for your safety, your inclination to leave may be correct. Lacking a crystal ball, you should do whatever seems necessary to protect yourself.

Q: Last year, I was contacted by a large international recruiting firm about a possible employment opportunity. Unfortunately, when I met with a recruiter from their local office, he said they couldn't work with me because my company was one of their largest clients.

The recruiter also mentioned that his manager and my boss were good friends, but he assured me that our conversation would remain confidential. However, when I turned in my resignation several months later, my boss informed me that his friend had told him I was looking.

Even though I recently changed jobs, this company continues to contact me. I have explained that I am very happy here, yet they keep calling me about other positions. I would like to tell them to buzz off, but they might be useful in the future. Why won't they leave me alone?

A: The reason for their persistence is simple. These folks are recruiters, and that's how recruiters work. When they have a position to fill, they keep trolling for candidates until they find qualified people to recommend. Despite your protests, they apparently hope the right opportunity might entice you to leave.

The next time someone calls, say that you appreciate their staying in touch, but you are not interested at the present time. Indicate that you will contact them if your circumstances change. When they call again, as they undoubtedly will, just repeat this script.

If you should ever decide to avail yourself of their services, consider requesting a signed confidentiality agreement. The previous lapse may simply represent the ethical shortcomings of a single manager, but it could also reflect a somewhat unprincipled corporate culture.