How To Work with A Colleague Who Undermines You (Without Losing Your Cool or Confidence)
We’ve all had coworkers who challenge us — but what happens when the challenge isn’t about the work, it’s about you? That one colleague who subtly (or not-so-subtly) chips away at your credibility, sows doubt about your abilities, or takes credit for your wins.
Undermining isn’t always loud. It can be dressed up as "helpfulness," sarcasm, or even fake concern. But make no mistake: it’s about power. And if left unchecked, it can seriously impact your confidence, your reputation, and your performance.
So how do you deal with someone who’s trying to make you look small — without becoming small yourself?
Let’s break it down.
First, Spot the Undermining Behavior
Undermining can be subtle, strategic, or straight-up shady. Here’s what it often looks like:
Interrupting or talking over you in meetings
Correcting you publicly, often over minor or incorrect things
Taking credit for your ideas or efforts
Withholding information you need to do your job
Spreading doubt about your competence or reliability
Undermining your authority in front of clients or junior staff
Gaslighting you with phrases like “I was just trying to help” or “You’re being too sensitive”
You’re not imagining it. And you’re not overreacting.
Step 1: Stay Grounded in Your Own Value
The first person you have to convince of your worth is you.
Take stock of your contributions, your strengths, and your wins. Keep a private “proof file” — notes of praise, successful projects, and receipts of your impact.
That’s not ego. That’s evidence.
Step 2: Document the Behavior (Yes, Seriously)
Start a running log. Dates, times, what was said or done, and how it affected your work. This isn’t just for HR — it’s for your own clarity. When things feel off, documentation gives you proof, not just vibes.
Bonus: If it escalates, you’ve already got the receipts.
Step 3: Set Boundaries — Professionally and Firmly
Call it out, calmly and directly, when it happens. Use assertive language, not aggressive.
Examples:
“Actually, I’d like to finish my thought.”
“Thanks, but I already addressed that in my earlier point.”
“I’d prefer if we discussed feedback one-on-one rather than in front of the team.”
“Going forward, please loop me in before representing my work.”
Bullies often back off when they know you’re not an easy target.
Step 4: Watch for Patterns — and Protect Your Reputation
Underminers often try to shift narratives. Protect your professional image by:
Looping in your manager on key updates
Following up important conversations in writing
Speaking up in meetings so your contributions are seen and heard
Collaborating visibly with others (so your work is undeniable)
In toxic cultures, visibility is sometimes your best defense.
Step 5: Build Strategic Allies
You don’t have to face abuse alone. Find trusted teammates or mentors who can validate your experiences, back you up, or even speak up when you’re interrupted or dismissed.
A little solidarity goes a long way — especially when your confidence is under attack.
Step 6: Know If and When To Escalate
If the behavior continues, it may be time to involve management. Share your documentation, be specific about the impact, and stick to the facts.
If leadership brushes it off or protects the underminer? That negligence tells you everything you need to know about the culture — and what you might need to do next.
You Deserve Better Than Subtle Sabotage
You didn’t get your role by accident. You didn’t earn respect to be picked apart by someone insecure. And you’re not too sensitive for noticing when someone is chipping away at your credibility.
You don’t have to play small just because someone else feels threatened by your light.
Hold your ground. Use your voice. Protect your peace — and your power.