ESG Reporting Frameworks Compared: GRI vs TCFD vs ISSB vs CDP

Australian organisations face a complex choice of sustainability reporting frameworks. GRI, TCFD, ISSB (now AASB S1 and S2 in Australia), and CDP each serve different purposes and audiences. For CFOs, finance teams, and sustainability managers deciding which frameworks to adopt, understanding their differences, overlaps, and complementarities is essential.

This guide provides a comprehensive comparison of the major ESG reporting frameworks and explains how Australian organisations can integrate them into a coherent sustainability reporting strategy. For broader ESG context, see our complete ESG guide.

Overview of Major ESG Reporting Frameworks

Before diving into detailed comparison, here is a brief overview of each framework:

• GRI Standards: Comprehensive, stakeholder-focused framework covering environmental, social, governance, human rights, and economic impacts across 300+ disclosure topics
• TCFD Framework: Climate-specific framework addressing governance, strategy, risk management, and metrics for climate-related financial disclosures
• ISSB Standards (AASB S1/S2): Investor-focused framework establishing mandatory sustainability-related financial disclosure requirements (AASB S1) with climate-specific standard (AASB S2)
• CDP Disclosure: Questionnaire-based platform enabling disclosure of climate, water, and forest risks to investors and stakeholders

Detailed Framework Comparison

Focus and Purpose

Mandatory vs Voluntary Status

Scope and Coverage

GRI Coverage

• 300+ disclosure topics spanning environment, social, governance
• Covers emissions, water, waste, biodiversity, labour practices, human rights, supply chain, product safety, community relations, anti-corruption, tax, governance
• Includes sector standards for specific industries
• Double materiality approach: impact materiality + financial materiality

TCFD Coverage

• Climate-specific: transition and physical risks
• Governance, strategy, risk management, metrics & targets
• Greenhouse gas emissions (Scope 1, 2, 3)
• Scenario analysis under different climate futures
• Climate targets and commitments

AASB S1 Coverage

• All material sustainability-related risks and opportunities affecting financial performance
• Governance, strategy, risk management, metrics & targets
• Materiality focused on financial impact and relevance to investors
• Similar structure to TCFD but applies to all sustainability matters, not just climate

AASB S2 Coverage

• Climate-specific application of AASB S1 framework
• Governance, strategy, risk management, metrics & targets for climate
• Mandatory Scope 1 & 2 emissions, Scope 3 where material
• Climate scenario analysis required
• Climate targets and progress tracking

CDP Coverage

• Climate Change: emissions, targets, governance, strategy
• Water Security: water risks, governance, targets
• Forests: deforestation risks in supply chain, governance, targets
• Questionnaire-based disclosure followed by scoring and benchmarking

Key Metrics Required

Assurance Requirements

• GRI: Encourages external assurance but does not mandate it. Common practice is to obtain assurance meeting international standards (ISAE 3000 or APES 3000)
• TCFD: Does not mandate assurance. Best practice includes assurance at some level
• AASB S1: Requires limited external assurance against APES 3000 (Assurance Engagements on Sustainability Information) for Group 1 entities
• AASB S2: Assurance requirement same as AASB S1 (limited assurance required for Group 1)
• CDP: Does not mandate assurance but verification improves scoring. Assurance is increasingly common for high-scoring organisations

Framework Interaction and Integration

How the Frameworks Work Together

Rather than competing, these frameworks increasingly complement each other. Here is how they interact:

• TCFD provides the climate framework: TCFD governance, strategy, risk management, and metrics form the basis for climate disclosure across all frameworks
• AASB S1/S2 provides mandatory baseline: For Australian Group 1 entities, AASB S1/S2 compliance is mandatory and effectively incorporates TCFD requirements plus broader sustainability matters
• GRI provides comprehensive context: GRI expands beyond financial materiality to impact materiality, covering labour, human rights, supply chain, and other topics not addressed in AASB S2
• CDP drives action on specific risks: CDP questionnaires on climate, water, and forests create investor engagement and facilitate benchmarking, encouraging target-setting and progress reporting

Sample Integrated Approach for Australian ASX-Listed Company

Mandatory:

• AASB S1 (General requirements) + AASB S2 (Climate-specific) for financial reporting compliance
• Limited assurance against APES 3000

Voluntary but recommended:

• GRI Standards for comprehensive stakeholder disclosure (environmental, social, labour, supply chain impacts)
• CDP Climate Change questionnaire for investor engagement and benchmarking
• Potentially CDP Water and Forests if material to operations or supply chains

Data integration strategy:

• Single materiality assessment capturing both financial materiality (AASB S1/TCFD) and impact materiality (GRI)
• Unified data collection for emissions, targets, governance meeting highest standards’ requirements
• Structured reporting with cross-referencing showing which disclosures address which framework requirements

Choosing Frameworks: Decision Framework

If Your Organisation Is:

Large ASX-listed company or Group 1 reporting entity:

• MUST comply: AASB S1 and S2 (mandatory from FY2025–26)
• SHOULD consider: GRI for broader stakeholder disclosure and CDP for investor engagement

Medium-sized company (Group 2 entity):

• Compliance deadline: AASB S1/S2 mandatory FY2026–27
• Voluntary: GRI and/or CDP if seeking competitive advantage or investor expectations require
• Recommendation: Begin preparation now to meet FY2026–27 deadline

Smaller company not in Group 1–3:

• No mandatory AASB reporting requirement (unless exceeding thresholds)
• Consider GRI and/or CDP if: customers/investors demand, industry peers use, supply chain pressure exists
• Recommendation: Monitor for future regulatory changes and assess whether voluntary reporting provides competitive advantage

Multinational organisation with international operations:

• AASB S1/S2 for Australian reporting requirements
• TCFD and/or ISSB S1/S2 if operating in jurisdictions adopting these (EU, UK, Canada)
• GRI for global stakeholder reporting consistency
• CDP for investor engagement across jurisdictions

Organisation in mining, agriculture, or financial services:

• GRI Sector Standards provide targeted guidance on industry-material topics
• All other frameworks apply as above based on size and geography

Practical Implementation Roadmap

Phase 1: Assessment (Months 1–2)

• Determine mandatory compliance obligations (AASB S1/S2 groups)
• Assess investor and stakeholder expectations (GRI, TCFD, CDP, etc.)
• Identify supply chain and customer requirements
• Benchmark against industry peers on framework adoption

Phase 2: Strategy (Months 2–4)

• Develop integrated materiality assessment covering both financial and impact materiality
• Select frameworks to adopt based on obligations and opportunities
• Plan integrated data collection and governance structures

Phase 3: Implementation (Months 4–12)

• Implement data collection systems meeting all selected frameworks’ requirements
• Establish governance structures for sustainability oversight
• Develop disclosure processes and quality controls
• Engage external assurance provider

Phase 4: Reporting and Iteration (Ongoing)

• Publish sustainability reports addressing selected frameworks
• Respond to TCFD, GRI, CDP requests/questionnaires
• Track performance against targets
• Continuously refine materiality and disclosure strategy

Frequently Asked Questions

Do we have to choose just one framework?

No. Most large organisations adopt multiple frameworks. AASB S1/S2 is mandatory for Group 1 entities, while GRI and CDP provide additional stakeholder and investor engagement value. Best practice is to integrate data collection and reporting across frameworks.

Is TCFD redundant now that we have AASB S2?

Not entirely. AASB S2 incorporates TCFD’s framework and goes further with mandatory assurance and prescribed metrics. However, TCFD’s guidance documents on scenario analysis and risk management remain valuable resources for implementation. Many organisations reference both.

Which framework should we prioritise if we’re new to sustainability reporting?

If you’re a Group 1 entity: start with AASB S1/S2 as it’s mandatory. If not yet subject to mandatory reporting: GRI provides a comprehensive starting point, or TCFD if climate is your primary focus. Consider investor expectations and stakeholder materiality.

Can we meet AASB S1/S2 requirements using just GRI and TCFD data?

Largely yes. GRI and TCFD data overlap significantly with AASB requirements. However, ensure your data collection explicitly addresses AASB S1 materiality definitions and S2 prescriptive metrics (Scope 1 & 2 mandatory, specific intensity formats, etc.).

How often should we update framework selections?

Annually review framework fit as: (1) your organisation evolves and materiality changes; (2) regulatory requirements shift (particularly AASB and other mandatory frameworks); (3) investor expectations evolve; (4) new frameworks emerge or existing ones are updated.

What’s the cost of multi-framework reporting?

Integrated approach is most cost-effective. Single, comprehensive materiality assessment and unified data collection meets multiple frameworks’ requirements. Cost scales with organisation size and complexity. Budget should include: systems/software, data collection labour, assurance, and external expertise as needed.

Moving Forward with Multi-Framework Strategy

Australian organisations navigating sustainability reporting should adopt a strategic, integrated approach to frameworks. AASB S1 and S2 compliance is mandatory for many entities and provides the baseline for investor-focused disclosure. GRI, TCFD, and CDP complement this with deeper stakeholder engagement, climate-specific guidance, and investor benchmarking. The key is building unified data systems and governance that allow organisations to meet multiple frameworks’ requirements efficiently without duplicating effort.

Ready to develop a framework strategy aligned with your organisation’s needs? Book a Free ESG Strategy Session to assess which frameworks apply to your organisation and plan integrated implementation.