Some specializations are difficult to replicate so we engage the very few who have mastered the skill.  Want to go to the moon?  Your list of vendors with those expertise is quite short.  Hoping to hold an event featuring US Presidents?  There are only a few individuals who have held the title.  These skills and achievements cannot be easily duplicated.  Therefore it is much easier to seek the services of those who have the knowledge than to try and replicate them ourselves.  What if your cause was the outright leader in an initiative?  This does not mean your enterprise is the largest, fastest, or most dominate.  It means that everyone turns to your organization to show them the way.  What if your expertise were so remarkable that how you shared them was the real gift?  Most communities have the doctor, tutor, trainer, or mechanic that people recommend as the expert when all else fails and the consequences are most significant. What do you have offer?