Folder security controls what reports a user has access to. A user (as a member of a role) has access to all documents in a folder once they are granted access to a folder.
To grant a role access to a folder, select a folder from the list and use the Grant Access button. Access to multiple folders may be granted at one time by using the control key to select multiple folders or by using the shift key to select a range of folders. The Grant Access button may be disabled if a role already has access to all folders.