First, start off with a QVW that contains all sheets. Right-click on the tab you want to hide from certain users and select "Sheet Properties." Under "Show Sheet", select "Conditional." As the condition, type is something like: QVUSER() = 'JOE'
It shows an altrnative for when you have a considerable amount of users. So instead of creating a condition like QVUSER() = X OR QVUSER() = Y ........ QVUSER() = N, yo create a Matrix that defines the proper access for each user.
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