Power to reduce or waive penalty: discretion to mitigate penalties where voluntary disclosure, cooperation, and genuine hardship are shown. Section 18B authorises the Commissioner to reduce or waive penalties where a person, prior to detection, has made a full and true voluntary disclosure, cooperated in assessment inquiries, and paid or made satisfactory arrangements for tax or interest; the Commissioner may also, on application and after recording reasons, reduce, waive, stay or compound recovery where refusal would cause genuine hardship and the assessee has cooperated; such orders are final and, in specified high-value concealment cases, may require prior higher-level approval.