You've been leading a high priority mission for months. You've pushed. Prodded. You've influenced internally because you believe it's the most vital issue facing your organization. Your team has invested sweat equity and they're counting on you to make it happen publicly.

At last, it's time to present your idea to an audience and influence others to take action. So what happens when you finally stand before your audience and take your swing at bat?

You get hijacked during Q&A.

It happened to the President of the United States on his home turf last week. At the end of his prime time health care news conference, Barack Obama answered a hot button question that was totally off-topic. Instead of asking about health care, a reporter asked the president what he thought of the confrontation between Harvard scholar Henry Louis Gates and Cambridge police officer James Crowley. The president weighed in with his opinion on race relations, ending with the tantalizing words "acted stupidly."

Bingo! Home run for the reporter! She'd successfully hijacked a presidential press conference. If this was a game of chess, she'd just pulled a capture: removing the opponent's piece or pawn from the board by taking it with one's own. The president's health care headline was toast. Now, the headlines were commandeered to scream of the 3 P's: the president, the professor and the police.

This is a living, breathing reminder to all of us to be mindful of Q&A so that our message doesn't become part of an opportunistic takeover - friendly or hostile.

Here are a few tips to help ensure that you don't hijack your own influence during Q&A:

• Don't answer too quickly. If the question is off-topic and hot button, don't allow yourself to be hijacked. Gently but firmly respond that the question is important but it's off-topic and will be best addressed during a more appropriate occasion. Offer a specific time when you will provide a thoughtful answer. The key is that you shouldn't appear to be dodging the question. You're simply deferring it to a more appropriate time and place.
• Keep your answer brief. The more you talk, the more likely you are to get caught up in your underwear and say something you'll regret. Long answers often lead to an unfortunate choice of words (think "acted stupidly") that can bite you in the backside. Talk less, but say more.
• Bridge back to your key points. The purpose of your presentation is to influence your audience and drive them to action. Never forget that. Use the audience's questions to reinforce your key points, not to steer the boat in a completely different direction.
• Don't let Q&A be the final word. Always have two closings. 1) The one that ends your prepared remarks before Q&A, and 2) the one that wraps everything up after Q&A. End with power and a strength of conviction that your message is high priority and actionable.
• Plan for hot topic tie-ins. You shouldn't be surprised in today's "anything goes" society. Think current events. What's on people's minds? Prepare, prepare, prepare.

As a communication coach, I guide senior executives in their high-profile presentations. As the day of their presentation draws near, I shift our focus from delivery of their key messages to preparation for high stakes Q&A. I ask every relevant question that I believe their audience might ask to ensure that the executive is influential in driving the ball forward, not backwards. Then, I slip on my broadcaster's cap and link their topic to other hot-button topics. This is an eye-opening exercise for executives who tell me it has saved them from embarrassment, being at a loss for words, saying something they'd later regret, and a loss of leadership influence. It boosts their confidence to handle anything that comes their way.

My inner Girl Scout constantly whispers the motto "Be prepared" in my ear. Never has that been more essential than in today's loosey-goosey world of Q&A.