Starting a conversation with these four words is sure to send most people into a panic: “We need to talk.” (Sorry for bringing up any bad memories.) But, unfortunately, conversations like these—whether in your personal or professional life—are unavoidable.

Here are three such difficult conversations—each starting with a different four words—that meeting planners may have to initiate.

“You’re no longer invited.” There could be a number of reasons you may need to tell an attendee, exhibitor, or other guest that they are no longer allowed to attend your meeting or convention. Among them: violating a meeting’s code of conduct or not meeting a convention’s eligibility requirements.

No matter the reason, rescinding an invite and explaining to a person why you have to cancel his registration is a discussion most people would not want to have, but it happens. And the more thoughtful you are with how you approach the uninvited attendee, the better the reaction he may have.

In this situation, it’s probably best to reach out via phone and explain the reasons for the person’s registration being cancelled, citing certain policies or eligibility requirements if need be. He will then have the opportunity to respond and give his feedback, and, even if he doesn’t agree with your decision, in the long run he may appreciate the personal outreach rather than a generic email telling him a refund is on the way.

“Attendance isn’t as projected.” So, you and your team put a lot of time and effort into creating a meeting that you were sure would drive high attendance numbers given past experiences or even member research. But then you open registration, and, well, let’s just say a few weeks in the numbers aren’t close to where you projected they’d be. Even worse: You’ve been called to your CEO’s office to update her on how things are going. Before you walk into the meeting, here are three factors to consider that may help you navigate the conversation better:

• Can lower numbers be attributed to a broader attendance trend like reduced travel budgets or attendees waiting until later to register? For example, do your events tend to attract federal employees?
• What other options do you have to promote attendance? Prior to the meeting, talk to other teams within your organization—like your marketing or social media groups—to see what other ideas may exist to draw more attention to the new event.
• What’s the worst-case scenario? Consider at what point it may make the most sense to cancel the meeting outright and the impact doing so may have. Know the current financial picture and what the breakeven point is in terms of revenue, because you will likely be asked both right away.

“The meeting is cancelled.” Speaking of worst-case scenario, sometimes it happens, and often it’s for reasons beyond your control: Thanks, Mother Nature! (But yeah for event-cancellation insurance.)

When it comes to letting your attendees and exhibitors know that a meeting is no longer taking place, the more communication the better, which is why a crisis communication plan is necessary.

Explain to registered attendees why you are cancelling, assure them that you understand that doing so may create some problems for them, and let them know how and when they can expect refunds and so forth. Also, be sure to communicate to them on multiple channels.

William Prentice, executive director of the Ambulatory Surgery Center Association, which held its meeting two days after the 2013 Boston Marathon bombing, has some other advice for planners:

“We try to war-game things out better now than we did prior to our Boston meeting. You don’t expect something like the Boston Marathon bombing to ever happen, but there are so many different things that could happen that could impede a meeting or create problems. Simulating those scenarios helps tremendously.”

If you’re looking for some more advice on how to approach tough conversations—meeting-related or not—these two articles featuring career coach Carol Vernon may be a good place to start.

What other difficult conversations have you encountered, and how did you handle them? Please share in the comments.