It is one thing to catch someone’s attention and another thing to hold it for as long as the speaker desires. There must be something about those leaders and speakers who have been able to achieve this feat. The secret is source credibility which arises from how the public view or perceive a speaker. This research paper explained the role of this important virtue in relation to advertisements, politics and religion. This paper is timely and significant because the most difficult form of management is human and mind management. The key is to be seen as a credible source. How is that possible?