Importers must conduct risk assessments of their international supply chains and ensure all business partners meet the C-TPAT security criteria. This includes verifying the security processes of partners through documentation, on-site visits, or questionnaires. Appropriate security measures must be implemented throughout the supply chain based on risk, including physical access controls, personnel security, procedural security, and cargo handling guidelines. Container integrity and inspection procedures must also be followed to prevent unauthorized access to cargo.