The skills you need guide to interpersonal skills

Authority
Sometimes, you may be able to persuade someone simply by virtue of your 
position. If you are in a position of authority, you can tell people what to do. 
This works very well in the armed forces, but any sales campaign that relies on 
‘experts’ to explain the benefits of a product is also using this type of strategy.
It is, however, a fairly limited strategy for long-term success as a manager or 
leader, because you cannot stand over people forever. Sooner or later, you will 
have to trust them to get on with it, and then they are unlikely to do so if they 
don’t believe in it themselves, but were only doing it because of your authority.