As sustainability reporting continues to evolve, organisations are increasingly expected to demonstrate not only what they report, but also how reliable that information is.
Investors, regulators, customers and other stakeholders are placing greater reliance on sustainability information when making decisions. As a result, many organisations are now seeking independent sustainability assurance to enhance confidence in the information they publish.
Alongside this growing demand, the International Auditing and Assurance Standards Board (IAASB) has introduced International Standard on Sustainability Assurance (ISSA) 5000 – the first international assurance standard developed specifically for sustainability information.
But what exactly is sustainability assurance, why has ISSA 5000 been introduced, and what does it mean for organisations?
What is sustainability assurance?
Sustainability assurance is an independent engagement performed by a qualified assurance practitioner to enhance confidence in an organisation’s reported sustainability information.
Much like an audit enhances confidence in financial statements, sustainability assurance enhances confidence that sustainability information has been prepared using suitable reporting criteria and is free from material misstatement. It provides greater confidence that the information is relevant, reliable and suitable for decision-making.
Depending on the engagement, assurance may cover:
- Greenhouse gas emissions
- Climate-related disclosures
- Biodiversity and nature reporting
- Workforce and social metrics
- Governance disclosures
- Broader sustainability reporting prepared under recognised reporting frameworks
Organisations may obtain either limited assurance or reasonable assurance, depending on their reporting objectives, stakeholder expectations and regulatory requirements.
Why is sustainability assurance becoming more important?
Over the last decade, sustainability reporting has expanded significantly.
Many organisations now report information using recognised reporting frameworks, while mandatory reporting and assurance requirements continue to develop across a growing number of jurisdictions. Investors and other stakeholders increasingly expect sustainability information to be supported by independent assurance before relying on it to make decisions.
As sustainability information becomes more closely connected to governance, strategy, risk management and financial reporting, organisations are placing greater emphasis on the quality, consistency and credibility of the information they disclose.
What is ISSA 5000?
ISSA 5000 is the IAASB’s first International Standard on Sustainability Assurance.
Unlike previous assurance standards that focused on individual sustainability topics, ISSA 5000 establishes a single global framework that can be applied to assurance engagements over sustainability information, regardless of:
- The sustainability reporting framework used
- The industry or sector;
- Whether reporting is voluntary or mandatory
- Whether the engagement provides limited or reasonable assurance
- Whether assurance is performed over a single entity or a group.
It is also a stand-alone standard, meaning it provides the requirements for planning, performing and reporting sustainability assurance engagements without requiring practitioners to apply other IAASB assurance standards alongside it, while still requiring appropriate ethical and quality management requirements to be met.
Why was a new assurance standard needed?
When ISAE 3410 was published in 2012, sustainability assurance was primarily focused on greenhouse gas emissions.
Today’s reporting landscape is very different.
Many organisations now disclose information covering climate, nature, biodiversity, workforce, governance and wider sustainability matters.
Rather than maintaining separate assurance standards for different sustainability topics, the IAASB developed ISSA 5000 to provide a single global framework capable of supporting assurance across all sustainability information. This helps promote greater consistency in assurance engagements while reducing fragmentation in global assurance practice.
From greenhouse gas assurance to sustainability assurance
“ISSA 5000 is more than a new assurance standard. It reflects the growing expectation that sustainability information should be supported by the same discipline, governance and evidence that organisations already apply to financial reporting.”
– Jose Hopkins, Chartered Accountant and Senior Sustainability Consultant, Acclaro Advisory
What does ISSA 5000 mean for organisations?
For organisations, ISSA 5000 represents an important step in the continued development of sustainability reporting.
It encourages organisations to look beyond the reported metrics themselves and consider the governance, reporting processes, evidence and internal controls that support the information being disclosed.
For many organisations, preparing for sustainability assurance is therefore not about introducing entirely new reporting systems. It is about strengthening existing processes, clarifying responsibilities and improving the quality of the information that supports external reporting.
Organisations that begin preparing early are likely to be better positioned as sustainability reporting and assurance expectations continue to evolve.
How Acclaro can help
Whether you’re preparing for your first sustainability assurance engagement or planning the transition to ISSA 5000, we can support you at every stage of the assurance journey.
- Pre-assurance readiness: Identify gaps in your reporting processes, evidence, governance and internal controls before assurance begins.
- Independent limited assurance: Deliver independent limited assurance over greenhouse gas emissions and other sustainability information in accordance with the applicable assurance standards.
- Post-assurance improvement: Provide practical recommendations to strengthen reporting processes, improve data quality and enhance assurance readiness for future reporting cycles.
If you’d like to discuss how ISSA 5000 could affect your organisation or your next assurance engagement, we’d be pleased to help.
