Authorised courier obligations: verify clients and file declarations to ensure customs compliance and prevent fraud. Authorised couriers must obtain client authorization for clearance (except for specified low value imports at delivery), file import/export declarations through qualified authorised agents, advise clients on customs law, verify client antecedents and IEC correctness using reliable independent documents (clients must furnish any two listed documents), exercise due diligence, maintain prescribed records, and not withhold information from clients or customs officers or improperly influence officers; these measures target fraud and duty evasion and enforce compliance with the Customs Act and related rules.