We've all had to have a tough conversation with someone we work with or for, and none of us likes it. Generally, we recognize that open, constructive communication is crucial to business success. But many dodge these chats at all costs. Others charge right in loaded and ready. Still others try to dance around the topic and not hurt feelings. None of these strategies is likely to accomplish your goal, so you end up where you started.

Joel Sparks, a freelance writer and owner of Original Copy in Silver Spring, Maryland, knows the feeling. "The hardest was firing a client," he recalls. "Every assignment was turning out to require unlimited revisions and meetings for a single low fee. It was also in a subject area that I was trying to phase out, but the projects just wouldn't end. Finally, in mid-deadline, I just had to tell them that I couldn't do it anymore. I had too much other stuff going on.

The result: "Now they won't speak with me," he says. "On the other hand, I'm writing the kinds of things I want to write now. I kept trying to be accommodating and nice, and that only made things worse in the end.

Lesson learned: "Say what you mean, and say it right away," advises Sparks.

Here are five additional tips for having effective and constructive conversations in difficult situations:

1. Give Fair Warning

The element of surprise won't work in your favor, says Loren Ekroth, Las Vegas-based founder of National Better Conversation Week. "You don't want to blind-side the other person, so ask them to get together at another time in a private, confidential place to clear up some issues. Let them know what you see as the issues and give them some time to reflect and prepare their thoughts for when you get together."

2. Have a Plan of Attack

"Consider what you want to say, write it down and sit with it for a while," says Suzanne Bates, author of Speak Like a CEO: Secrets for Commanding Attention and Getting Results and president of Bates Communications in Wellesley, Massachusetts. "Writing it down will help you act, instead of react. If you're not sure what you want to say, discuss it with someone you trust. Be sure that person can be trusted not to disclose it. Confidentiality is critical. You don't want to complicate the situation."

3. Be Prepared for an Ongoing Process

Be ready to have to continue the conversation later, cautions Alexander Grashow, director of the consulting practice at Cambridge Leadership Associates in Cambridge, Massachusetts. "Difficult conversations are iterative and most often require the people involved to negotiate changes with their people, departments or communities."

4. Call for a Mediator

If you think the conversation will become heated, ask that a mutual, trusted colleague be present to mediate and keep things civil, Ekroth suggests. "Often the simple presence of another puts antagonists on their best behavior so differences can be worked out with civility."

5. Check Assumptions at the Door

Making too many assumptions is a common mistake, Bates says. "It's easy to assume we fully understand the other person's motivation," she says. "We are too quick to jump to conclusions about people's actions, behaviors and attitudes." To avoid that, forget about who is right and focus on understanding the other person. "Be genuinely curious," she advises. "This will help you get clarity. Separating fact from assumptions is the key to arriving at real understanding. Questions also interrupt the blame game and create an atmosphere of trust instead of suspicion."

Armed with these tips, you'll be ready the next time you have to have a tough talk with a colleague or client. And you'll be more likely to achieve a positive outcome for everyone.