I have a workbook with many sheets with identical format and similar data. I
need to have cells and ranges named, but the names need to be local to a
particular worksheet.

I've accomplished that in the past by setting up one worksheet, naming
everything to my liking, then making a copy of the worksheet. In the copy,
all the names are nicely qualified with the name of the sheet.

I've done that, and now I need to expand the worksheets. I can't find a way
to add new names and make them local to any sheet. I don't want to go through
the copy process again due to the the impact on other sheets that collect
data from all these other sheet.