If you do not want to give VIEW permission to the staff member to see all clients, you can assign a staff member as an administrator to one or more specific clients.

Go to the Customer profile from the admin area and click on the Customer Admins tab.

Click on the assign admin button and choose the member/s you want to be assigned as admins to this specific customer.

Save the changes.

The member/s you assigned will be able to see how this customer together with the Customer menu item without having permission for customer VIEW.