It fascinates me the subtle differences in the words efficacious, effective, and efficient. It was introduced to me in one of my Myers Briggs books.

According to Webster …
effective: producing a decided, decisive, or desired effect <an effective policy>
efficient: being or involving the immediate agent in producing an effect <the efficient action of heat in changing water to steam>
efficacious: having the power or capability to produce a desired effect <an efficacious remedy>

Additional meaning …
effective stresses the actual production of or the power to produce an effect … more focused on the fact that there was a good result rather than who or what was caused the good result.
efficient suggests an acting or a potential for action or use in such a way as to avoid loss or waste of energy in effecting, producing, or functioning … so something that saves time.
efficacious suggests that you possess of a special quality or virtue that gives effective power. This is how individuals ought to think about how they add value and be givers. That they possess something special and unique, something that only could have come from their unique, lifelong journey.

personal power
Yes, a cheesy picture from Google Images

People in this world are producing results and saving time constantly … but what are the results and time savings that the world gets from the efficacious you? What’s the contribution (big or small) that you could make efficaciously?