Communication effectiveness

Effective Communication... the key or the locK?

I believe effective communication is everything.  I think that if an individual is able to communicate effectively then there ability to create and access opportunities in life is enhanced.  Their capacity to resolve disputes and negotiate positive outcomes from most situations is almost assured. 

Have you ever been engaged with or by an effective communicator?  You feel like you've been better understood, had an opportunity to state your position or point of view and are crystal clear on the other parties perspective.