The AA1000 Assurance Standard (AA1000AS v3) serves as a standard for assurance on sustainability information across organisations of all types, based on the effective application of the AA1000 AccountAbility Principles (AA1000AP, 2018). As shown in Figure 1, the AA1000AP (2018) forms the core of the AA1000 Standards Series and is designed to be subject to external assurance by AccountAbility-licensed assurance providers1 using the AA1000AS v3 while also providing the foundation for the AA1000 Stakeholder Engagement Standard (AA1000SES), AccountAbility’s globally leading standard for high-quality stakeholder engagement. The AA1000AS v3 provides a holistic way of holding an organisation accountable for its sustainability management, performance, and reporting practices by assessing the adherence of the organisation to the AA1000AP (2018). Intended to go well beyond simple data verification, the AA1000AS v3 focuses on the processes required for responsible and complete assurance engagements based on the AA1000AP (2018) Principles of Inclusivity, Materiality, Responsiveness, and Impact.