GRCI

What Is ISAE 3000 Training?

ISAE 3000 training is professional development in IAASB International Standard on Assurance Engagements 3000 (Revised) — the international standard governing assurance engagements on subject matters other than historical financial information. It covers sustainability assurance, ESG reporting verification, non-financial information assurance, and the general assurance engagement methodology required under CSRD.

ISAE 3000 is the assurance standard that goes beyond financial reporting. It governs all assurance engagements where an auditor is expressing a conclusion on subject matter other than historical financial information — sustainability reports, GHG emissions statements, ESG disclosures, internal control effectiveness, and agreed-upon procedures engagements.

In 2026, ISAE 3000 has become critical knowledge for UK assurance professionals as CSRD (Corporate Sustainability Reporting Directive) requires limited or reasonable assurance on sustainability information. UK audit firms, assurance providers, and corporate sustainability teams urgently need ISAE 3000 competency — and very few training providers offer it at practitioner level.

ISAE 3000 Course Curriculum

The ISAE 3000 curriculum covers the standard's complete framework with particular depth on sustainability assurance:

The ISAE 3000 Standard

ISAE 3000 (Revised) structure and key requirements
ISAE 3000 vs ISAE 3402 vs ISA 315/ISA 330: when each applies
Direct and attestation engagements under ISAE 3000
Professional ethics and independence requirements for ISAE 3000 engagements

Engagement Design

Defining the subject matter: what can be assured under ISAE 3000
Criteria: suitability, availability, and criteria characteristics
Limited vs reasonable assurance: scope, procedures, and conclusion differences
Engagement acceptance and continuance: preconditions and risk assessment

Sustainability & ESG Assurance

CSRD and ESRS: what assurance is required and when
GHG Protocol and ISO 14064: assuring Scope 1, 2, and 3 emissions
Double materiality assessment: its role in assurance scope
TCFD, TNFD, and voluntary framework disclosures under ISAE 3000

Evidence and Procedures

Designing an ISAE 3000 work programme for sustainability assurance
Evidence types for non-financial information: challenges and solutions
Applying analytical procedures to ESG data
Documentation standards for ISAE 3000 engagements

Reporting

Limited assurance report structure under ISAE 3000
Reasonable assurance report structure and opinion wording
Modified conclusions: qualified, adverse, and disclaimer of conclusion
Communicating ISAE 3000 findings to boards, audit committees, and investors

Module

What You Will Learn

Module 1: ISAE 3000 Foundations

Understand ISAE 3000 (Revised) purpose, scope, and relationship to ISAE 3402 and SOC 2. Covers the IAASB standard, types of assurance engagements, and when ISAE 3000 applies versus other assurance standards.

Module 2: Assurance Engagement Structure

Master the components of an ISAE 3000 engagement — responsible party, practitioner, intended users, subject matter, criteria, and conclusion types (limited vs reasonable assurance).

Module 3: Sustainability & ESG Assurance

Apply ISAE 3000 to sustainability reporting assurance under CSRD. Covers GHG emissions verification, ESG disclosure assurance, ESRS (European Sustainability Reporting Standards), and limited vs reasonable assurance conclusions on sustainability information.

Module 4: Evidence & Procedures

Design and execute assurance procedures appropriate for non-financial subject matter — inquiry, analytical procedures, inspection, recalculation, and external confirmation for sustainability and ESG assurance engagements.

Module 5: Reporting & Conclusions

Draft ISAE 3000 assurance reports — limited assurance conclusions, reasonable assurance opinions, and emphasis of matter paragraphs. Understand how conclusions are communicated to different stakeholder groups.

Module 6: CSRD Implementation Readiness

Prepare assurance teams and corporate sustainability departments for CSRD-mandated assurance. Covers ESRS requirements, double materiality assessment, and the phased transition from limited to reasonable assurance.

Why Choose GRC Index for ISAE 3000 Training?

GRC Index offers dedicated ISAE 3000 training alongside ISAE 3402 and SOC 2 training — the only UK CPD-certified provider covering all three IAASB and AICPA assurance standards in a single training portfolio, enabling professionals to understand when each standard applies. Our ISAE 3000 training has a particular focus on sustainability assurance under CSRD — the most significant new application of ISAE 3000 for UK assurance professionals and corporate sustainability teams in 2026.

Advantage

Detail

CSRD Sustainability Assurance Focus

The only UK training course with dedicated CSRD and ESRS content within an ISAE 3000 practitioner framework

ISAE 3000 Specialist Depth

Dedicated ISAE 3000 practitioner training — not a paragraph in a general sustainability course

All Three Standards Covered

Offered alongside ISAE 3402 and SOC 2 training — understand when each standard applies

First-Mover Advantage

Very limited UK competition in dedicated ISAE 3000 practitioner training — establish authority now

CPD-Certified — 12 Hours

Recognised for ICAEW, ACCA, IIA, and other professional body CPD requirements

Professional Role

Why This Course Matters

Audit Partners & Senior Managers at Accounting Firms

Develop ISAE 3000 sustainability assurance competency to serve clients with CSRD assurance requirements — a growing revenue line for UK audit firms

Sustainability Assurance Practitioners

Practitioners specialising in ESG verification, GHG emissions assurance, and non-financial reporting require ISAE 3000 as their primary standards framework

Corporate Sustainability Directors & Teams

Understand CSRD assurance requirements from the corporate perspective — what assurance providers will test and how to prepare sustainability disclosures

Internal Auditors

Extend assurance capabilities beyond financial reporting — apply ISAE 3000 methodology to internal assurance reviews of ESG data, GHG reporting, and sustainability governance

Risk & Compliance Officers

Understand ISAE 3000 assurance obligations in the context of CSRD, TCFD, and emerging sustainability disclosure requirements

Finance Teams Supporting Sustainability Reporting

Finance professionals responsible for CSRD sustainability data quality and assurance readiness

Frequently Asked Questions: ISAE 3000 Training

What is ISAE 3000 training?

ISAE 3000 training is professional development in IAASB International Standard on Assurance Engagements 3000 (Revised) — the international standard for assurance engagements on subject matters other than historical financial information. It covers sustainability assurance, ESG disclosure verification, non-financial information assurance, and general assurance engagement methodology.

What is the difference between ISAE 3000 and ISAE 3402?

ISAE 3402 is specifically for assurance on service organisation controls relevant to financial reporting. ISAE 3000 is the broader general assurance standard applicable to any subject matter other than historical financial information — including sustainability reports, GHG emissions, ESG disclosures, and agreed-upon procedures engagements. ISAE 3402 is a specific application within the broader ISAE 3000 framework.

Why is ISAE 3000 important for CSRD compliance?

The EU Corporate Sustainability Reporting Directive (CSRD) requires limited or reasonable assurance on sustainability information reported under the European Sustainability Reporting Standards (ESRS). ISAE 3000 is the primary assurance standard for CSRD sustainability assurance engagements. UK organisations within CSRD scope and their assurance providers require ISAE 3000 competency to comply.

What is limited vs reasonable assurance under ISAE 3000?

Limited assurance under ISAE 3000 results in a negative form conclusion ("nothing has come to our attention") based on limited procedures. Reasonable assurance results in a positive conclusion ("the subject matter is fairly presented") based on more extensive testing. CSRD initially requires limited assurance, transitioning to reasonable assurance over time. GRC Index training covers both levels in detail.

Who needs ISAE 3000 training in the UK?

ISAE 3000 training is essential for audit partners and senior managers at accounting firms developing sustainability assurance services, sustainability assurance practitioners, corporate sustainability directors preparing for CSRD assurance, internal auditors extending their assurance capabilities, and compliance teams managing CSRD disclosure obligations.

Is ISAE 3000 the same as ISAE 3402?

No. ISAE 3000 is the general international assurance standard for subject matters other than historical financial information — including sustainability, ESG, and non-financial reporting. ISAE 3402 is a specific standard derived from ISAE 3000, applicable only to service organisation controls relevant to user entities' financial statements. Both standards are part of the IAASB assurance framework. GRC Index offers dedicated training for each.

ISAE 3000 Training