"Credibility is the foundation of leadership," says James Kouzes, author of Credibility: How Leaders Gain and Lose It, Why People Demand It. "If people don't believe in the messenger, they won't believe the message."

In business, if you lack credibility, you may never be able to get a team to follow you and it will be difficult to advance to a position of authority. Let's face it: If people don't believe what you say, nothing else really matters.

Your credibility is based on your words and actions. If these two areas of communication are incongruent, your credibility will suffer. So if you are a team member who says you will help out but never do, your credibility will diminish as a result.

Whether you're sharing information or job recognition, if you are not credible, it will be of little consequence. If you expect others to believe what you say, you first have to believe it yourself.

Five Mistakes That Damage Your Credibility

Every leader and potential leader needs to avoid five specific mistakes to maintain credibility. So don't:

• Fail to Keep Up with Your Field of Expertise: No matter what field you're in, there are almost always changes. And if you don't stay abreast of the advances, others will see you as a weak leader. People want to follow leaders who are current, knowledgeable and confident. If you don't know your field, your credibility suffers, because you're no longer believable.
  
• Withhold Information: Good leaders and team members do not keep information from others. When you withhold information, it is perceived as being controlling at best, lying at worst.
  
• Neglect to Tell the Truth: Lying to your staff and customers or fellow employees is always a terrible idea. "Leaders and those aspiring to be leaders must recognize that self-serving behavior is the trail to organizational suicide," Kouzes says. Be honest with others, and you will better serve yourself and your organization in the long run.
  
• Try to Get People to Like You Rather Than Respect You: Typically, a person who is trying to be liked rather than respected is perceived as insincere, phony and noncredible. Building likeability is no more than being a glad-hander. These people run into meetings all smiles and try to shake hands with everyone, but they are not the least bit interested in anyone or anything other than their own agendas.
  
• Refuse to Accept Personal Responsibility: If you're not willing to accept personal responsibility for what you do, then you will lose credibility. Others will perceive you as fake or a self-serving jerk. "Leaders, whether in the boardroom or on the front line, are at the center of a vast web of relationships," Kouzes says. "Leaders must reach out and attend to all their constituents if they wish to be credible… credibility, like quality and service, is determined by the constituents, so leaders must be able to view themselves as their constituents do."

No matter who you are or where you are within your organization, you must build credibility and steer clear of all that will destroy it. Consider this your number one priority throughout your career, and promise yourself you will never get caught in a situation that forces you to compromise your credibility.