I think I already have a pretty firm grasp of ByVal and ByRef, but I
checked out the article anyway. I don't think it addresses my
problem.

In short, here's what happens:
Let's say I write  a Public function in the code  module of my user
form that returns the value of a text box in that form. If I write a
function in a different module  in the Modules folder of the project
and then try to call that text box return  function, it says that the
function is undefined. No mention of trouble with arguments.

Any more ideas?