Assurance of sustainability reporting cover



Feb. 23 2024

Governments, investors, partners, consumers, and other stakeholders are stepping up the pressure on companies to integrate environmental and social issues. With sustainability reports playing a strategic role in this setting, the information they contain has got to be reliable. 

Mark Fraser, Sustainability Business Development Manager at Bureau Veritas Certification Global Business Line, tells us about the vital job performed by third-party assurance in tackling this challenge: “We provide assurance that the information contained in a company’s sustainability report is accurate, relevant, complete and consistent.” 

Fraser goes on to sum up the objective of the Bureau Veritas Assurance of Sustainability Reports (ASR) Service as: "An independent assurance report against recognized standards that demonstrates an organisation’s commitment to customers and stakeholders alike. It provides a level of comfort to key decision-makers, who know that the information they use for business decisions and strategy is reliable and complies with relevant reporting frameworks."


The assurance process comprises four core phases:

Assurance of Sustainability Report session
  1. Scoping and planning - confirming reporting scope and timelines with the client.
  2. Detailed assurance - requesting information from client, and conducting preliminary data review and client interviews.
  3. Internal delivery and completion - conducting an in-depth data and process review and closing out any remaining open issues, and an independent review and internal sign-off within the assurance team.

4.   External delivery - the client receives their assurance opinion statement (for public use, usually within the sustainability report) and management report (for internal use to help with improvement planning for the next reporting cycle).

These reports address inherently broad and complex themes. With Europe’s new Corporate Sustainability Reporting Directive (CSRD) slated to come into effect in 2025 for reports covering FY 2024, the complexity level is set to go up yet another notch. This won't just affect Europe’s largest companies, but also any UK businesses that are selling into or have a presence in Europe.

Getting reporting right relies on bringing recognized expertise to bear, which is then checked by assurance practitioners, providing an extra layer of trust to the report user, whether they are an investment analyst, customer or regulator. Bureau Veritas experts tackle a series of tasks to make this happen, as Fraser explains: 

We sample data, follow audit trails and interview key staff responsible for areas of material sustainability impact, risk or opportunity, or as data owners.”


To fully demonstrate an organisation’s commitment to its customers and stakeholders, an independent assurance statement also needs to meet recognized standards. This affords a level of comfort to decision-makers, who can be confident that the information they use for business decisions is dependable and aligned with relevant reporting frameworks.

To this end, Bureau Veritas experts assess sustainability reports written to align with a range of international standards and frameworks, such as the Global Reporting Initiative (GRI), International Sustainability Standards Board (ISSB) and Task Force on Climate Related Financial Disclosures (TCFD). Bureau Veritas has a strict policy on impartiality and follows accepted international assurance standards ISAE 3000 and AA 1000 AS, which also require extensive ethical integrity, such as independence from conflicts of interest. These standards detail the best-practice approach to conduct an assurance engagement. Having the right personnel is critical, Fraser confirms: 

Mark Fraser from Bureau Veritas

Sustainability Business Development Manager

Bureau Veritas Certification Global Business Line

"We choose a competent team. We train our people thoroughly. They have sector knowledge requirements and often technical specializations, such as Diversity Equality and Inclusion (DE&I), Greenhouse Gas (GHG) emissions verification or Health and Safety (H&S)."

At the end of each job, an “independent technical review” check is performed by another assurance practitioner who was not involved in that particular client’s engagement, to make sure that procedure has been followed, and that a conclusion has been reached based on actual evidence that has been reviewed by the assurance team.

Case study: pharmaceuticals

Bureau Veritas’ client, a global household name in pharmaceuticals, needed to build reliability and stakeholder confidence on sustainability data and reporting: 200 KPIs published in the Sustainability Data Summary (selected data and text claims included in the Annual Report and TCFD Report). The scope of the solution included their global operations and spanned all environmental and social data. Bureau Veritas’ experienced sustainability team provided a robust and efficient global assurance process as per the ISAE 3000 standard. 

The continued partnership over a 10-year period and Bureau Veritas’ resulting experience with their existing systems ensured smooth project management. Bureau Veritas has delivered assurance statements to be published in their annual sustainability report in line with the ISAE 3000 standard requirements. Management reports detailing the findings were also provided, identifying genuine opportunities and challenges to inform internal stakeholders’ efforts to continue improving their sustainability.

boots on the ground

To provide an even higher level of assurance, some providers, including Bureau Veritas, draw on broader know-how. What separates Bureau Veritas from its competitors is its “boots on the ground”, says Fraser, “our inherently practical approach backed up by people with expert backgrounds.” 

Bureau Veritas teams include sustainability assurance practitioners with further educational qualifications in relevant ESG topics and experience with monitoring and reporting systems, rather than auditors with a financial reporting background. All of which offers additional assurance to companies that the information they provide to their stakeholders is reliable, robust and can be fully trusted.