Report Access Rights
You can define user rights to access the report as well as report availability in certain application screens in the Roles and Screens tab of the report editor.
If the Resource roles list contains at least one role, the report will be available only to users with this role. If no role is specified, the report is available to everyone.
Keep in mind that in the reports browser (the Reports→Reports menu item) all system reports are visible because this screen is considered administrative.