The best way to ensure continuous compliance with security requirements is to conduct periodic reviews of the vendor’s third-party accredited assessments (B). From a CISM governance and third-party risk management perspective, ongoing assurance is critical when business-critical functions are outsourced. Independent third-party assessments (such as SOC reports or equivalent accredited reviews) provide objective, repeatable, and evidence-based validation that security controls are not only defined but are operating effectively over time.

Training programs (A) improve awareness but do not provide assurance of compliance. Establishing right-to-audit clauses (C) is an important contractual safeguard, but it is typically reactive or periodic, not a continuous monitoring mechanism. Re-approving contract clauses (D) ensures contractual relevance but does not validate actual control effectiveness.

CISM emphasizes that continuous vendor compliance is best achieved through independent assurance mechanisms integrated into ongoing vendor oversight, enabling management to monitor control effectiveness, identify emerging risks, and take timely corrective action. Periodic review of accredited third-party assessments supports governance transparency, accountability, and alignment with the organization’s risk appetite.