A presentation is a tool made of words and numbers, information and opinions. In many circumstances, its purpose is to help an audience make a decision or a prediction.

But the source of those words, the speaker, must be trusted by the audience. One of the first questions you should ask yourself when preparing a high-stakes presentation is, "Who should deliver it?"

A few years ago a client asked me to help prepare a presentation to a regulatory body in Washington, D.C. If the presentation was successful, it would earn the company hundreds of millions of dollars, and we believed, save the lives of many children.

Several accomplished senior executives volunteered to deliver the talk, but we selected two young women, both Ph.Ds in chemistry. One was a free-spirited Californian with a radiant smile, the other born in the heart of Brooklyn with an accent to prove it. They both knew the science cold and cared about the people who would be impacted by the decision.

The executives we passed over had a few things going against them. First, they weren't research scientists, and the regulatory body was made of nothing but. Second, they were men, and might have given off a whiff of marketing swagger. There's nothing devoted scientists loathe more than marketing swagger and the reek of exaggerated claims.

Furthermore, the regulators were all men, and the women we chose to present the data were warm and highly competent people who would not attempt to dominate their listeners. They got results by being humble, polite, and precise in the language they used.

For instance, they began their presentation with something like this: "We are pleased that you are willing to hear an argument for XYZ. It is our intention to convince you of the following three points..." and here they listed the points, which for reasons of privacy I will not mention.

"We will take turns because the data is complex and each of us has mastered about half of the story. Plus, a little variety in the scenery might keep you more engaged. Shall we begin?"

Long story short, they won. They were asking for something that had never been done before, and they managed to get approval. The company was granted the right to proceed, saved many lives, and made a bunch of money.

One of the first questions you need to ask when delivering a major, high-stakes presentation like the one described above, is, "Who should deliver the talk?" The senior people in your organization may lay claim to their right to be the presenter, but they may not be the strongest choice.

In the theater world they say that casting is nine-tenths of directing. In the world of high-stakes business presentations, a speaker has a better chance of getting what she wants if the audience trusts her and her motives.