Before a difficult conversation, script your opening line. Say it out loud once beforehand.

Why it works: The first line sets the tone for everything that follows — get that right and the rest tends to follow.

Use it: Before any conversation you've been putting off.

One person can set the mood for your entire team.

Not because they're the most senior.

Not because they're right more often than everyone else.

Because everyone around them has learned that managing them is easier than challenging them.

You've watched it happen.

Someone waters down a point before they've even finished saying it.

The next person checks that person's face before answering a question that wasn't even meant for them.

A decision goes ahead, and instead of relief in the room, there's a flicker of dread. Everyone already knows how this will land, and they're bracing for it.

Meetings run shorter than they should, because nobody wants to be the one who sets them off.

You've noticed all of this.

You've chosen to ignore it, because it isn't happening to you, and you've decided everyone else is tough enough to handle it themselves.

I think this is easy to let slide because it's your team who pays for it, not you.

When one person on your team is unpredictable — sharp, moody, quick to sulk or snap — everyone else adapts.

Not because you told them to.

Because adapting feels safer than confronting it.

They stop raising certain topics. They soften what they want to say before they've even opened their mouth. They start managing someone else's reaction instead of just doing their job.

One person's mood becomes the whole team's weather system.

It's a form of emotional contagion (the way one person's state spreads through a group without anyone consciously choosing it).

Teams are especially vulnerable to it, because everyone's watching everyone else for cues on what's safe to say.

And it keeps running because you're not the one dealing with it.

You're not the one adjusting what you say in every meeting.

You're not the one who dreads Mondays, wondering which version of that person is going to show up.

So it's easy to rationalise.

"They're not like that with me."
"It's probably just a personality clash."
"I don't want to make it bigger than it is."

It's already bigger than you think.

Every person adjusting their behaviour around one bad mood is quietly learning that you'll let it keep happening.

You don't need to fix this person's personality.

You need to protect the room.

The first time, keep it simple. Not weeks later. Not in a vague team email.

"I won't have people in my team spoken to like that. Let's talk about what happened."

If it's happened before, name it as a pattern.

"This has happened more than once now. I need to understand what's driving it, and I need it to stop."

Next you need to address the atmosphere it leaves behind.

People can disagree with a decision. They don't get to make everyone else pay for it afterwards.

"You can disagree with the decision. You don't get to make the room pay for it."

Not to gossip. So they know you've seen it.

"I've noticed how that conversation went. That's not something you need to manage on your own."

This person might be brilliant at their job. That doesn't make their mood the team's problem to manage.

"How good you are at your job doesn't buy you the right to decide how everyone else feels today."

I've coached leaders who let talent excuse this for years. Every one of them wished they'd stepped in sooner.

Managing the individual is half the job.

Protecting everyone else from them is the other half.

Stop telling yourself this isn't your problem because it isn't happening to you.

It's happening in your team.

That makes it your problem.