Audit by tax authorities allows officers to examine records, demand assistance and trigger recovery action for tax discrepancies. The Commissioner or authorised officers may audit any registered person in prescribed manner, at business premises or office, after at least fifteen working days' notice. Audits should be completed within a three-month audit period, extendable by the Commissioner for stated reasons. Commencement of audit is the later of records being made available or actual institution of the audit. Officers may access books, require information and assistance. The proper officer must communicate findings, reasons, rights and obligations within thirty days, and detected tax discrepancies may trigger initiation of recovery proceedings.