Glossary›Assurance, audit evidence and working papers›Group assurance and component assurers
Glossary term
Cluster A · A44
Tier 1 · differentiator
Group assurance and component assurers
Definition
Group assurance is the assurance of sustainability information covering a parent and its controlled entities. Where sites or subsidiaries are assured by another firm, that firm is a component practitioner. Under ASSA 5000 the group engagement leader remains responsible for the conclusion and must be sufficiently involved in the work of any component practitioner they rely on.
On this page
In practice
Australian captured entities are frequently groups with operations across states and often across borders, and the emissions data arrives from entities that have never been inside a group audit scope before. Group assurance is where that structure bites.
ASSA 5000 draws a distinction that matters commercially. A component practitioner is a firm the group engagement leader can be sufficiently involved with, usually a network firm, or a firm that will accept the group leader’s direction and give access to its working papers. Another practitioner is a firm the group leader cannot be sufficiently involved with. The consequence is direct: work done by a component practitioner can support the group conclusion; work done by another practitioner generally cannot be relied on in the same way, and the group leader has to do the work themselves or scope the component out.
The practical trap is the local assurance an overseas or joint-venture subsidiary already buys. Entities assume it counts. It usually does not, either because the firm will not accept group direction, or because the local engagement was performed to a different standard, a different materiality and a different period.
The second trap is scoping. The group leader selects which components to visit and test based on the group materiality and the risk each component carries. A component that is 4% of group revenue can be 40% of group Scope 1 emissions. Components are scoped for assurance on their emissions significance, not their financial significance, so the sites that get visited are often not the ones the CFO expects.
What the assurer does with it
The group engagement leader determines group materiality, identifies components, and decides for each whether to perform the work centrally, use a component practitioner, or scope it out with a documented basis.
Where they use a component practitioner they communicate the scope, the materiality, the criteria and the reporting deadline in writing, then review the component’s work. They will require access to the component practitioner’s documentation, and they will visit or hold working meetings with the significant ones.
What they reject is a component assurance report handed over as a finished product with no access to the file behind it. “Our German subsidiary is already assured locally” is not evidence for the group conclusion unless the group leader can get sufficiently involved in that work.
The procedure that generates the most first-year friction is the group’s own consolidation. The assurer tests whether the components reported add up to the group figure, on the same boundary, for the same period, with intra-group activity treated consistently. Where the group has used operational control for emissions and a different consolidation basis for the financial statements, they will ask for a documented reconciliation of the two entity populations.
Commonly confused with
The organisational boundary. The boundary decides which entities are inside the emissions inventory. Group assurance scoping decides which of those entities the assurer tests. A site can be inside the boundary and never visited, and that is normal, not a gap.
Sources
1
ASSA 5000 General Requirements for Sustainability Assurance Engagements
AUASB
2
Review status
Review required
Last reviewed
15 September 2026
Editorial pass, unsigned
Reviewer required
Registered company auditor
Next scheduled review
1 July 2027
Part of
Cluster A, Assurance, audit evidence and working papers
47 terms on what an assurance provider tests, what they accept as evidence, and what a preparer has to be able to produce.
Related terms
What decides which entities are in the inventory at all
The group definition that drives capture
What an unreachable component becomes
Related questions
What is our organisational boundary and who decides it?
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Your organisational boundary is the set of entities and facilities whose emissions you report, and the basis on which you include them. Management decides it, the board or audit committee approves it, and it should reconcile to the consolidated entity in your financial report. Operational control is the common Australian starting point, and the friction sits in joint ventures, leased sites, franchises and recent acquisitions.
Do our subsidiaries have to report separately or does the parent cover them?
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Each entity is tested on its own. A subsidiary that must lodge its own financial report under Chapter 2M and meets a section 292A test prepares its own sustainability report, even where the parent reports as well. Being consolidated into the parent’s report does not by itself remove the obligation.
What does an assurance provider actually test in year one?
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In year one they test the disclosures inside the ASSA 5010 first-year scope: Scope 1 and Scope 2 emissions, governance disclosures, and specified strategy paragraphs on climate risks and opportunities. The work runs in a predictable order, from understanding your reporting process and your boundary, through sampling source documents and reperforming calculations, to written representations at the end.
Other terms in this cluster
Group assurance and component assurers