A Buyer’s Guide to Assurance on Sustainability Information

WBCSD and ICAEW have updated the Buyer’s Guide to Assurance on Sustainability Information, building on the first edition published in 2019.

The sustainability reporting and assurance landscape has evolved rapidly. Regulatory requirements, investor expectations and governance demands have significantly increased the need for credible, decision-useful sustainability information and robust assurance over it.
This updated guide reflects that shift. It positions assurance not only as a compliance requirement, but as a strategic tool to strengthen governance, improve data quality and support better decision-making.

What this guide provides

The guide offers practical, buyer-focused guidance for organisations seeking to understand, prepare for and obtain assurance on sustainability information. It supports organisations across the full assurance journey:

• Understanding assurance fundamentals (what assurance is and what it is not)
• Defining assurance needs and scope based on user needs and materiality
• Assessing organizational readiness and planning a phased assurance journey
• Selecting and engaging assurance providers
• Working effectively with assurance practitioners throughout the engagement

It is designed for corporate buyers responsible for commissioning and overseeing assurance, including sustainability, finance, audit and governance functions, as well as board and audit committee members.