Linking "pick list fields" that are the same.

Linking "pick list fields" that are the same.

Question:  When using a "pick list" field that is the same in multiple files is there a way to only have to add new values to one of them?
 
For example;  We're using Lead Source in both the Leads file and the Potentiasl file.    If we add a new Lead Source option in the pick list, we currently have to remember to add the value in the other files as well.
 
Thank you for your help!

Jere Warner

610.828.8630 x4101