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It’s a small, small world in professional circles. That can be great for you as you prove yourself and work your way up. It can also turn your work life into a horror movie sequel as the villain, Toxic Boss or Colleague Who Makes You Pick Up All the Slack, strikes again.

But the bottom line is that you’re likely to encounter some people more than once throughout your career—whether they’re your former office buddy you can’t wait to be cubicle neighbors with again, the worst boss you’ve ever had, or that really nice colleague who just couldn’t get their act together.

And some of these people might apply for a job at your current company. Or they might apply elsewhere and a friend, recruiter, or hiring manager doing their research might reach out to ask for a back-channel reference.

So, what do you do?


What to Do If it Was a Toxic Personality Thing



If a former co-worker you didn’t love is applying to a job at your current company, the first thing to ask yourself is whether you’d feel comfortable working with this person again, says Muse Career Coach Yolanda Owens. If it was a toxic boss or a cruel colleague and the answer’s something along the lines of “under no circumstances” or “that would be my worst nightmare”? Then Owens says “sing like Patti LaBelle.”

“A toxic person could completely change cultural dynamic,” she explains. “I think I would feel kind of a moral responsibility and self-care responsibility to say something about that,” she adds, whether or not someone explicitly asked for your feedback. Be honest, but professional.


A toxic person could completely change cultural dynamic. I think I would feel kind of a moral responsibility and self-care responsibility to say something about that. Yolanda Owens


The safest bet is to approach the recruiter, if your company has one, she says. But if you’ve been at the company for a while, established a solid reputation, and built a strong relationship with the hiring manager, you might consider approaching them directly.

If you have to be the whistleblower, Muse Career Coach Leto Papadopoulos says, the most professional and helpful way to relay such feedback is to give actual examples. Owens agrees, emphasizing that you should be strategic about your examples. If you talk about how this person’s behavior affected not only you, but also other colleagues, it’s less likely to come off as a personal vendetta.

And if you are asked directly by someone at your own company or elsewhere, definitely don’t lie and say that person’s great, Papadopoulos says. Because if they come in and behave terribly, “in the end I will look bad, and it’s going to hurt my current company” or that of the friend asking.


Try Phrases Like…

“I understand you’re interviewing [person]. I know you didn’t explicitly ask for my feedback. But I do feel it’s important to give a little feedback from my experience with that person for their candidacy.”

“These are some behaviors/patterns/red flags I noticed that I think you should be aware of…”

“[Person] may not be a good fit for this organization.”

“I have to tell you, I know this person, I know their work. Here’s what happened… I’m afraid they might not be the right fit.”

“I would be very disappointed if this ended up happening here. This is great place to work.”


What to Do If it Was a Performance Issue



It’s not just huge jerks that might give you pause. You might’ve worked with someone who was super nice, funny, or pleasant to be around, but they just never met their deadlines or always turned in sloppy work or made tons of mistakes. If the issue was related to performance, Papadopoulos and Owens say the situation is less dire.


Be as soft as possible. Give the person an opportunity. Leto Papadopoulos


Remember that people can grow and improve, especially if it’s been years since you last worked with them. You probably don’t need to volunteer information about past performance issues. But if someone asks you explicitly, especially within your own company or a close friend, it might be worth saying something, Papadopoulos says. But “be as soft as possible. Give the person an opportunity.”


Try Phrases Like…

“I did work with this person before. There were some performance issues but it’s completely possible that they’ve worked on it. Here’s what was going on when I worked with them…”

“This was a great person. However, I did notice a few patterns with this individual in terms of…”

“I don’t want you to just base it on my word but might suggest adding questions that would address this kind of issue for this candidate and future candidates.”


What to Do No Matter What


Be Professional

No matter how horrible an experience you had with a former co-worker, remember that how you talk about them and how you articulate your feedback reflects on you. You don’t want to become known as the tattletale or the gossiper, or be seen as immature or unprofessional.

And remember that “it’s not about getting retribution or vengeance,” Owens says. “The important thing is, again, making sure the person is making an informed decision.”


Take Time to Prepare Your Feedback

“First and foremost, I wouldn’t answer the question immediately,” Owens says. If someone reaches out to you, acknowledge that you received their request and let them know you’ll get back to them in a day or two. Take some time to get over any initial impulse or emotional reaction you might have and prepare a thoughtful answer.


Ask Yourself How Much You Know and Trust the Person You’re Talking To

The difficult truth is that if the co-worker in question is someone who’s both very awful and very powerful, and word gets back to them, it might hurt you. Or if your feedback is otherwise repeated in a less professional way or without context, it could affect your own reputation.

“I would hope if it was my own workplace, they wouldn’t throw me under bus for it,” Papadopoulos says. The same goes for a close friend working at another organization.


I’d be really wary of sharing that kind of detail with someone don’t know or trust. Yolanda Owens


But it gets trickier when you don’t know the person asking well, or at all. Before you say anything, ask yourself how much you trust them. You can always opt to say very little, such as, “This isn’t someone I could recommend,” and leave it at that.

You might also decide to decline to speak about your former co-worker entirely. “I’d be really wary of sharing that kind of detail with someone don’t know or trust,” Owens says, because you can’t be sure they won’t use your name later. In that case, you can just say, “I wouldn’t be comfortable speaking about that person but I appreciate you reaching out.”


Plan to Speak in Person, or at Least on the Phone, and Off the Record

Even if you’ve decided you trust someone enough to give some honest feedback, both Papadopoulos and Owens caution against putting anything in writing. In other words, don’t do this over email. The best approach would be to have a conversation in person. Ask the recruiter or hiring manager if you can schedule 15 minutes to sit down one on one. Or, if you’re not in the same office, set up a phone call.

Owens also suggests explicitly saying you want the information you’re sharing to stay just between you. You can tell them, “I’m happy to share as long as this is completely off the record.”


No one wants to face a revival of their worst workplace experience (with original cast members!). And no one wants to hire someone who will end up bringing down the morale of a team or company. So it can be crucial to both sides that you pass on some honest feedback about people you’ve worked with in the past. You’ve just got to be careful how you do it. So read this, rehearse, and take a deep breath before you do.