The ISO Environmental Management International Plenary 2025 marked a pivotal moment for global environmental governance. Held in Toronto from October 25 through November 1, the meeting brought together experts, professionals and leaders to discuss key developments in environmental management standards. Among its many discussions, the plenary served as the first official occasion to launch the partnership between GHG Protocol and ISO, aimed at delivering unified global standards for greenhouse gas (GHG) emissions accounting.

At the plenary, GHG Protocol and ISO formally announced that they will be convening a Joint Working Group (JWG) to co-develop the new product-level GHG accounting standard. This represents an important milestone in the continued harmonization of international GHG accounting frameworks. As part of this effort, GHG Protocol opened a call for experts to join the JWG alongside ISO experts, ensuring broad and diverse stakeholder participation in shaping the technical development of the standards.

The meeting also launched parallel work to align corporate and project-level accounting standards, including those from the ISO 1406X family and the GHG Protocol corporate suite. This broader initiative aims to deliver greater consistency across the global reporting landscape, strengthening credibility and compatibility for organizations of all types.  

Throughout the discussions, participants from ISO and GHG Protocol reaffirmed a shared commitment to produce future-ready, scientifically-grounded standards that meet the needs of companies, regulators, and stakeholders worldwide.  

Building on this shared commitment, the partnership took a major step forward at COP30. GHG Protocol and ISO formally launched the Plan to Harmonize Global Carbon Accounting Standards in a workshop at COP30 hosted by the COP30 Presidency, alongside the High-Level Champions, Ministry of Foreign Affairs of Brazil and UNIDO. GHG Protocol and ISO have been recognized as the key implementation partners for harmonized carbon accounting standards across the corporate, project and product level by the COP30 Presidency and UN Climate High-Level Champions within the COP30 Action Agenda, following the Presidency's call for robust carbon accounting frameworks. You can read more about this announcement in coverage from the World Economic Forum and the Climate Herald.

Harmonizing standards is foundational to accelerating global climate action. By aligning methodologies and principles, GHG Protocol and ISO are enabling businesses, governments and stakeholders to take decisions with clarity and confidence. This alignment will accelerate decarbonization and drive systemic change at scale.

For more information about the partnership, please see our Frequently Asked Questions resource.