A case study: Demystifying materiality in accordance with ISSA 5000

At a glance

Understand how ISSA 5000 applies materiality to sustainability assurance engagements.
Learn practical approaches for setting thresholds, judging disclosures and managing assurance risk.
Gain confidence delivering credible sustainability assurance and reducing greenwashing concerns.

Report by:

ACCA and Chartered Accountants ANZ

As focus sharpens on ensuring the credibility and trustworthiness of increased sustainability reporting by businesses, ACCA and Chartered Accountants ANZ have joined forces to provide a practical guide to key requirements of the new International Standard on Sustainability Assurance 5000 (ISSA 5000).

This follows the publication of ISSA 5000 by the International Auditing and Assurance Standards Board (IAASB) for sustainability assurance engagements, which aims to increase trust in sustainability reporting and reduce the risk of greenwashing. Sustainability reporting is increasing around the world as more countries make it mandatory, especially for larger businesses.

ACCA and Chartered Accountants ANZ have collaborated to plan a series of practical guides to some of the key requirements of the standard. This is the first in the series and it focuses on materiality.

Additionally, the guide recommends that practitioners recognise the importance of the materiality stage in an assurance engagement and the various professional judgement points that are involved, ensuring that they allocate sufficient time to applying the requirements appropriately, including the relevant documentation requirements. The results of the materiality stage will assist the practitioner in developing the approach to obtaining evidence and when evaluating any misstatements in sustainability reporting.

The guide provides guidance through a fictional assurance engagement and is structured around the application of materiality to Scope 1, 2 and 3 greenhouse gas (GHG) emissions.

ISSA 5000: Demystifying the assurance of estimates

This case study explores the assurance of estimates and forward-looking information to promote a consistent and proportionate approach.

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The trust and confidence of investors, regulators and other stakeholders in sustainability assurance is vital if sustainability reporting is to be successful in bringing about a more sustainable approach to business.

Antonis Diolas

Head of Audit and Assurance at ACCA

The case study

Outlines the applicable ISSA 5000 requirements and the various professional judgement points involved in considering or determining materiality for qualitative and quantitative disclosures respectively.
Demonstrates the assurance practitioner’s considerations when setting thresholds, benchmarks and performance materiality.
Explores an approach to grouping disclosures logically based on similarity in expression, user interest and user tolerance for misstatement.
Supports assurance practitioners in assessing the needs and expectations of intended users.Guides the addressing of aggregation risk in assurance engagements.
Navigates application of double materiality in accordance with European Sustainability Reporting Standards (ESRSs).

Key requirements of ISSA 5000

The latest development in sustainability reporting – the publication by the International Auditing and Assurance Standards Board (IAASB) of ISSA 5000 – aims to establish a global baseline for sustainability assurance engagements. In this session, we will look at the key requirements in ISSA 5000, General Requirements for Sustainability Assurance Engagements, and what the implications will be for preparers and assurers.

Materiality is no longer a buzzword – it’s the backbone of credible sustainability assurance. This guide offers clarity where it’s most needed. As sustainability reporting and assurance become mandatory across jurisdictions, ISSA 5000 sets the global baseline – and this guide helps practitioners apply it with confidence.

Amir Ghandar

Reporting and Assurance Leader at CA ANZ