One other note, I'm not at all sure that "folders" is what I'm after.
Just so that we are on the same page, when I navigate to View Arrange
By Current View Customize View - a diolog box pops up. On that
dialog box is a button labled "Filter", which if cicked, bring up
another dialog box. In the Filter dialog box is a tab called Advanced.
On this tab is a drop down option called "Fields". One of the options
in that dropdown is "All Appointment Fields" with a sub option of
"Categories".

Best possible solution: We create a macro which, when executed, brings
up the Filter dialog box with the Advanced tab pre-selected, and
"Categories" pre-populated in the Fields form.

Is this do-able?

Thank you!!!

Casey