Thanks, Tom.

Yes,

worksheets("sheetName").Buttons("cmdName").enabled = false

works fine, because this button was created from the Forms toolbar.
However, I'm still looking for a way to "gray-out" the button, or provide
some other visual cue when it's disabled. When I only set the enable
property to false, the button's appearance doesn't change in any way, and
the cursor still changes to the white hand when it's placed over the button,
implying that it's active, even though it isn't.

Do you know of a way to provide a visual cue that the button is disabled
without making it invisible?