Climate change, social impacts, and governance are increasingly becoming part of business decision-making. Investors, regulators, and society want to know not only how companies generate profits, but also how they manage their sustainability-related impacts and risks. As this need grows, so does the importance of reliable sustainability information—and the question of whether the information reported can be trusted. 

A sustainability report may look comprehensive, but that does not necessarily mean it provides sufficient information for its intended users. The question, therefore, is: how much confidence can users place in the information when making decisions? This is where sustainability assurance plays an important role. 

Why Does Sustainability Assurance Matter? 

Sustainability assurance is an engagement designed to enhance the confidence of intended users in sustainability information. The practitioner provides an opinion or conclusion based on evidence obtained, rather than simply confirming that a report appears complete or follows a particular format. 

Assurance does not mean that the practitioner guarantees every piece of sustainability information is free from error. Its objective is to obtain reasonable assurance or limited assurance about whether the information is free from material misstatement, and to communicate the result in a written report. 

The Emergence of ISSA 5000 

To support the consistency and quality of these engagements, the International Auditing and Assurance Standards Board (IAASB) issued the International Standard on Sustainability Assurance (ISSA) 5000. The standard provides a framework for assurance engagements over sustainability information, whether prepared under a reporting framework or other suitable criteria. 

A key feature of ISSA 5000 is that it is a single, principle-based standard. Rather than prescribing one fixed set of procedures for every engagement, it establishes principles and requirements that practitioners apply through professional judgment. This allows the nature, timing, and extent of procedures to be tailored to the circumstances of the engagement, including the entity’s characteristics, the complexity of the information, and the level of assurance provided. 

What Does It Cover? 

ISSA 5000 applies to different forms of sustainability information, both quantitative and qualitative. It also covers reasonable assurance and limited assurance engagements, and can be applied to both listed entities and entities other than listed entities. 

Sustainability assurance is therefore not limited to one type of report or one particular topic. An engagement may cover an entire sustainability report, selected information, a specific topic, or a particular aspect of a topic, depending on the agreed scope. 

Accountability Already Exists 

One of the distinctive features of sustainability assurance is the variety of information involved. In addition to figures and indicators, practitioners may examine narratives, targets, policies, and disclosures about sustainability-related impacts and risks. 

The process therefore requires an understanding of the entity, risk assessment, materiality considerations, and evaluation of relevant evidence. These activities form part of an end-to-end engagement, from acceptance and continuance through to reporting. 

Building Stronger Confidence 

Ultimately, sustainability assurance is not only about issuing an assurance report. Confidence is built through a supporting ecosystem: a suitable reporting framework, robust assurance standards, and relevant ethical and independence requirements. Together, these elements help make sustainability information relevant, reliable, credible, and comparable. 

ISSA 5000 Adoption in Indonesia 

In Indonesia, SAKb 5000 adopts ISSA 5000, issued by the International Auditing and Assurance Standards Board (IAASB), and is aligned with the Indonesian regulatory framework and assurance practices. The standard is intended to provide a comprehensive framework for practitioners in performing sustainability assurance engagements and to support the consistent delivery of high-quality assurance. 

As part of the adoption process, the Indonesian Institute of Public Accountants (IAPI) approved the issuance of the Exposure Draft (ED) SAKb 5000 – General Requirements for Sustainability Assurance Engagements on 20 July 2026 for public consultation. This development marks an important step toward establishing a locally appli-cable framework for sustainability assurance in Indonesia. 

Ultimately, sustainability assurance is not just about checking a report, but about building confidence in infor-mation that is becoming increasingly important to the future of business. 

 

Contributors: Tyas Widianti & August Christian, Audit Practice