Hi

Maybe have an extra sheet that has the name of the sheets in the workbook, and the user id that can access them. You could use that to determine what sheets are visible for which user.

If a new sheet is created, then it would be added to that list. A beforeclose and beforesave event could check the list of visible sheets against this stored list, and if there is a sheet on the store, that isn't visible, then it could be removed from the store.

HTH

rylo