From Framework to Practice: Navigating IFRS S1, S2, and the New Sector Guidance That Will Define Credible Climate Reporting

International Financial Reporting Standards (IFRS) S1 and S2 published by the International Sustainability Standards Board (ISSB) in June 2023 and effective for annual reporting periods beginning on or after 1 January 2024 are not simply another sustainability checklist. They represent a structural shift in how sustainability information is positioned: not as a corporate social responsibility (CSR) appendix, but as investor-relevant financial information, subject to the same governance and assurance expectations as financial statements.

IFRS S1 sets general requirements for sustainability-related financial disclosures. It asks companies to disclose information about all sustainability-related risks and opportunities that could reasonably be expected to affect their cash flows, access to finance, or cost of capital.

It is built on four pillars borrowed from the Task Force on Climate-related Financial Disclosures (TCFD): Governance, Strategy, Risk Management, and Metrics and Targets.

IFRS S2 is the climate-specific standard. It builds on S1’s architecture and adds concrete requirements: Scope 1, 2, and 3 greenhouse gas (GHG) emissions disclosure, physical and transition risk scenario analysis, and cross-industry metric categories covering carbon, energy, water, waste, and capital deployment aligned with climate commitments.

Importantly, under both S1 and S2, companies are required to refer to and consider the Sustainability Accounting Standards Board (SASB) Standards when identifying relevant sustainability topics. The companies applying ISSB Standards are expected to refer to and consider SASB standards, which cover 77 industries and specific standards mapped to them.

The Sector Guidance Revolution: What Changed in 2026
This is where 2026 becomes critically important. The ISSB has been systematically enhancing the SASB Standards as part of its 2024–2026 workplan, responding to stakeholder feedback that generic frameworks were insufficient for industry-specific reporting.

In July 2025, the ISSB published an exposure draft proposing amendments to nine priority SASB sectors, including financial services, technology, and extractives. Then, on 26 March 2026, a second exposure draft was published covering the three remaining prioritized sectors: Agricultural Products; Meat, Poultry, and Dairy; and Electric Utilities and Power Generators. The comment period closes on 24 July 2026.

The changes are not cosmetic. The amendments aim to improve international applicability, synchronize terminology with ISSB Standards, and improve interoperability with frameworks including the European Sustainability Reporting Standards (ESRS), the Global Reporting Initiative (GRI), and the Taskforce on Nature-related Financial Disclosures (TNFD).

The Three Pillars Most Companies Are Getting Wrong

Pillar 1: Materiality — Not Everything Is Material, But You Must Prove It

IFRS S1 uses a ‘financial materiality’ standard: a sustainability topic is material if omitting or misstating it could reasonably affect the decisions of primary users of general-purpose financial reports that is, investors. This is a narrower test than the European Union’s (EU) ‘double materiality’ under the Corporate Sustainability Reporting Directive (CSRD), which also captures a company’s impact on the world.

The risk is that companies either over-disclose, creating noise and litigation exposure, or under-disclose, creating regulatory and credibility risk. The discipline of IFRS S1 is that every disclosed topic must be supported by a documented materiality assessment. In practice, this means building a materiality process that is auditable, stakeholder-informed, and updated annually.

China’s disclosure regime is evolving differently from the ISSB baseline and may incorporate broader impact-oriented expectations in some areas.

Pillar 2: Scenario Analysis — The Requirement Nobody Reads Carefully Enough

IFRS S2 requires companies to disclose how their business strategy and financial planning consider climate-related risks and opportunities under different scenarios, including a scenario consistent with limiting global warming to 1.5°C above pre-industrial levels. This is both a qualitative and quantitative requirement and it is the pillar where most companies in emerging markets are furthest from compliance.

A 2025 peer-reviewed study covering 89 annual and sustainability reports from the energy, chemicals, and construction materials sectors found that risk management and metrics disclosures particularly quantitative climate impact assessments, remain ‘substantially underdeveloped’ across emerging markets. Governance and strategy disclosures showed higher alignment, but the operational and financial linkages required under S2 are largely absent.

For companies in Malaysia, Indonesia, Vietnam, and the Philippines, jurisdictions rapidly moving toward ISSB alignment and this is not a theoretical gap. It is the gap between being ISSB-aware and being ISSB-ready.

Pillar 3: Scope 3 and Cross-Industry Metrics — Where Assurance Will Eventually Land

Both S1 and S2 require companies to report on Scope 3 GHG emissions – those that occur across the entire value chain. This is the most contested metric in ISSB implementation, particularly for companies in Asia whose Scope 3 exposure spans multiple jurisdictions, multiple regulatory environments, and multiple data-maturity levels among suppliers.

Australia has taken a pragmatic approach: Group 1 and 2 entities must report Scope 3 under the Australian Sustainability Reporting Standards (ASRS), but with a three-year transition period during which Scope 3 data carries modified liability protections. This is a model worth watching for other ISSB-aligned jurisdictions managing the tension between completeness and auditability.

What the SASB Sector Guidance Means in Practice
The enhancements to SASB Standards are the single most underappreciated development in ISSB implementation in 2026. Here is why they matter:

• For financial institutions (banks, insurers, asset managers): The enhanced SASB financial sector standards clarify how financed emissions (Scope 3 Category 15, investments) should be measured and disclosed. For Asian banks with large loan portfolios in high-carbon sectors, this is no longer guidance. It is a disclosure expectation.
• For the agriculture and food sector: The March 2026 exposure draft targeting Agricultural Products; Meat, Poultry, and Dairy directly affect companies across Southeast Asia, Brazil, and Australia, regions where agriculture is both economically dominant and climatically exposed. The amendments introduce clearer metrics on water usage, land use, and GHG intensity per product unit.
• For power utilities and electric generators: As Asia races to build data centre capacity to meet AI demand, the enhanced Electric Utilities standards apply pressure on power companies to disclose renewable energy mix, grid reliability, and carbon intensity. Singapore, Malaysia, and Australia are already navigating this intersection.

The Asia-Pacific Readiness Gap: A Region in Transition
By mid-2025, more than 30 jurisdictions representing over 60% of global gross domestic product (GDP) had committed to adopting or aligning with IFRS S1 and S2. Yet for most companies in the region, implementation remains at the governance and strategy disclosure layers. The harder work which is the quantitative risk assessment, Scope 3 data collection, and scenario analysis is largely incomplete.

Taiwan (95%) and South Korea (76%) stand out with the highest SASB adoption rates in the Asia-Pacific region, reflecting strong uptake of industry-specific standards even as broader regulatory frameworks evolve. China’s CSDS, while ISSB-aligned on single financial materiality at present has introduced impact considerations that put it closer to the EU approach, creating dual compliance challenges for multinationals.

The practical implication: companies that have spent 2024–2025 building governance frameworks and strategy disclosures must now shift their focus to the harder data work – metrics, scenario analysis, and sector-specific disclosures. The ISSB’s sector guidance update is the signal that this phase has begun.

ESG-BI PERSPECTIVE
Stop treating IFRS S1 and S2 as a compliance checklist and start treating them as an enterprise data architecture problem. But more data doesn’t necessarily mean “better readiness”. It is good to have ambition, but what’s more important is to gain “operational maturity” by putting in place repeatable internal controls, clearer accountability, and better integration between sustainability, finance, risk, and operations. In short, the companies that will lead on ISSB implementation are not those with the longest sustainability reports, but those with the most defensible systems for materiality, data collection, scenario analysis and sector mapping. Our specific guidance for members in Asia-Pacific:

First, build a materiality assessment process that is documented, auditable, and updated annually. A desk-based exercise that has not involved your board or your investors will not survive regulatory or investor scrutiny.

Second, map your disclosures to the relevant SASB sector standard before deciding what to report. The sector guidance tells you what investors actually want to see, not what is easiest to produce.

Third, start Scope 3 data collection now. Do it imperfectly if necessary. Regulators and investors reward direction of travel over perfection. The companies that have not started will face a structural disadvantage when assurance requirements arrive.

Finally, engage the ISSB’s consultation on the March 2026 SASB exposure draft before 24 July 2026. This is your opportunity to influence the sector guidance your industry will be measured against for the next decade. Most companies in Asia are not taking it. That is a strategic mistake.