When supporting materials serve persuasion, they become evidence. Facts and statistics alert us to a situation that we must change. Examples move listeners, creating a favorable emotional atmosphere for the speaker’s recommendations. Narratives bring a sense of reality, and help listeners identify with the issue. Testimony calls upon witnesses to support a position. When you use evidence, strive for recent facts and figures, emphasize factual examples, engage listeners through stories that make your point, and rely primarily on expert testimony.