Hey thanks for the response Bob. I have reviewed the help information. What I don't get is what is the meaning of "Empty"? I know what NULL is...

A users interpretation of Empty is if they do not see any characters, then it's Empty. I tend to agree. It appears that the MM.NET framework BLG does not interprete it this way when building rules. I just hate to have to over-ride the generated code worrying that a rule for an Empty string will not indicate the string is Empty (no visible characters).