Power in human communications and relations is determined largely by the interplay of our unconscious minds, according to Nick Morgan in his book Power Cues: The Subtle Science of Leading Groups, Persuading Others, and Maximising Your Personal Impact. If you can understand how that unconscious interplay works and exercise some control over it, you may become more effective in the ways you relate to other people.
My full review of the book is available at my business book reviews website.