The Integrity Council for the Voluntary Carbon Market has published a new report from its Continuous Improvement Work Program (CIWP) on the Oversight of Validation and Verification Bodies (VVBs). 

VVBs play a critical role in the functioning of carbon markets. As independent third-party entities, they validate mitigation activity design and verify greenhouse gas emission reductions and removals against carbon-crediting program requirements, providing the technical basis for project registration and credit issuance decisions. Yet there can be a disconnect between the role VVBs are formally assigned and how that role is understood by market participants and the public, with VVBs often perceived as having broader responsibilities than those defined within the carbon market oversight framework. 

Recognising the importance of these issues, the Integrity Council convened a diverse group of experts and stakeholders from across the carbon market ecosystem to explore how oversight of VVBs can be strengthened and how confidence in assurance systems can be maintained and/or improved as carbon markets scale. Participants included accreditation bodies, VVBs, carbon-crediting programs, project developers, Indigenous Peoples’ representatives, human rights specialists, researchers and other market experts.  

“As carbon markets evolve, so too do expectations and requirements of validation and verification. One of the key insights from this work program was that confidence in the market depends not only on the performance of individual VVBs, but on the effectiveness of the broader ecosystem surrounding them. By bringing together diverse perspectives from across that ecosystem, the work program identified practical opportunities to strengthen transparency, accountability and coordination, supporting more consistent and credible outcomes across the market.” – Jessica Wade-Murphy, CIWP Co-Facilitator and ICVCM Expert Panel Co-Chair.  

Oversight challenges in a growing carbon market 

The CIWP identified several interconnected challenges affecting VVB oversight and performance across the market. These include questions around the boundaries of VVB responsibilities, differences in oversight approaches across carbon-crediting programs, shortages of VVBs and qualified auditors, competency requirements for assessing safeguards and sustainable development impacts, conflict of interest management and transparency in validation and verification outcomes.   

The working group found that many of these challenges cannot be addressed by any single actor alone. VVBs operate within a broader ecosystem involving accreditation bodies, carbon-crediting programs, international standards and market participants. Strengthening oversight therefore requires a system-wide approach that recognises the complementary roles and responsibilities of each part of that ecosystem.  

As one of the report’s central findings notes, existing standards and program-level controls provide important safeguards, but inconsistencies in implementation, capacity constraints and evolving expectations -particularly around safeguards and sustainable development -can create risks to overseeing potential assessment quality issues and market confidence.  

Key outcomes of the CIWP 

The report presents ten recommendations aimed at strengthening the oversight of VVBs and improving confidence in validation and verification systems across carbon markets. While some recommendations are directed at the Integrity Council and future evolution of the CCP Assessment Framework, others are aimed at carbon-crediting programs, accreditation bodies and VVBs themselves. 

At a high level, the recommendations focus on four key areas: 

Greater transparency and accountability 

The report calls for stronger transparency around VVB performance, oversight activities, and validation and verification outcomes. Recommendations include establishing minimum reporting requirements for CCP-Eligible programs, improving comparability of oversight practices, and strengthening transparency around project status, audit outcomes, and performance trends.  

Stronger oversight and coordination 

Participants highlighted the importance of coordinated, risk-based oversight that combines the strengths of the oversight from carbon-crediting programs and from accreditation bodies. The report recommends enhanced information-sharing, clearer oversight expectations and improved coordination to avoid duplication, close oversight gaps, and support more effective supervision of VVB performance.  

Building competencies for a more complex market 

As carbon markets increasingly incorporate safeguards, sustainable development requirements and more diverse project types, assurance activities require expertise that extends beyond greenhouse gas accounting alone. The report recommends strengthening competency requirements across the assurance ecosystem, including broader expertise in environmental and social safeguards, sustainable development impacts, and local context. It also highlights the need to expand and upskill the global pool of qualified auditors.  

Managing conflicts of interest and strengthening confidence 

The report also explores measures to reinforce impartiality and address both actual and perceived conflicts of interest in validation and verification activities. Recommendations include clearer rules on auditor independence, conflict of interest management, and greater coordination across programs to ensure issues identified in one context are visible across the broader system.  

 “Our discussions highlighted that scaling high-integrity carbon markets requires balancing robust control with deep technical competence. Crucially, this expertise must extend beyond VVBs to the programs and accreditation bodies overseeing complex safeguards and assessment quality. These ten grounded recommendations combine our collective strengths, providing the practical framework needed to build system-wide capacity and scale with absolute confidence.” – Javier Castro, CIWP Co-Facilitator and ICVCM Expert Panel member 

Implications for the future of carbon market integrity 

Beyond its individual recommendations, the report’s overarching message is that strengthening VVB oversight is essential to supporting high-integrity carbon markets at scale. 

The CIWP highlights that assurance systems must continue to evolve alongside growing market expectations. This includes clarifying the role of VVBs, ensuring assurance teams have access to the right expertise, improving transparency, and strengthening coordination between oversight actors. The report also identifies opportunities to leverage digitalisation and emerging technologies to improve efficiency, comparability, and oversight outcomes in the future.  

Many recommendations emphasise practical improvements that can deliver more consistent validation and verification outcomes while helping markets scale with confidence. Together, they seek to support a system that is not only robust and credible today, but also capable of adapting to future expectations and innovations. 

Looking ahead 

The findings from this CIWP will help inform future refinement of the CCP Assessment Framework while also highlighting actions that can be taken by carbon-crediting programs, accreditation bodies, VVBs, and other market participants. The work will also feed into related Integrity Council initiatives, including the ongoing CIWP on Digital Measurement, Reporting and Verification (DMRV).  

By bringing together diverse expertise from across the carbon market ecosystem, the CIWP has provided a series of practical recommendations for strengthening one of the most important pillars of carbon market integrity. As demand for high-quality carbon credits grows, effective oversight of validation and verification bodies will remain central to building trust, confidence and accountability across the market.