If you're challenged by a colleague or by management on a statement you've made, here's a couple of tips:

1. Make sure your statement is backed up by facts. This is something you do before opening your mouth.

2. Acknowledge the question, comment or criticism. The first way of winning over an opposing viewpoint is through acknowledgement.

3. Paraphrase what they've said. Again, you're working on coming to a middle ground, rather than being on opposing terms. If the middle ground doesn't happen, then agree to disagree.

4. Be honest and open that you don't agree and clarify why you're sticking to your statement. Make sure you have both your facts ready, and that you know what you are talking about. People, especially seasoned players, can smell a fraud a mile away.

5. Back your facts with empirical or strong anecdotal evidence.

6. Close in with a short sentence summarizing your statement. If you're doing this in front of an audience, you can invite them to the discussion. Use nonverbal cues such as eye contact or an inviting hand gesture (this works if you have a passionately engaged audience), or ask if anyone else wants to add to the discussion.

You will most likely win the other person's respect by standing your ground and asserting yourself in a firm, non-aggressive manner. It helps to back your statements with facts and an audience of engaged colleagues who support your stance.

Don't be afraid of anyone's position of power. They are human too.

Ultimately, you will win their respect if you play your cards right.

This tip is based on my personal experience. Its also fine to agree with them if their viewpoint is fair and accurate. It's not a contest.