SystemESG & Sustainability Reporting

ESG Data Assurance Readiness

ISSA 5000 readiness, figure by figure: every number an assurer will test, traced and fixed before fieldwork

Every figure an assurer will test, traced and fixed before fieldwork starts.

See one case, screen by screen ↓
demo146figuresin assurance scope on the sample statement, each traced through five layers — 127 ready
demo+223tCO2eScope 2 understatement found by re-performing 25 site-months against invoices, three weeks before fieldwork
target9 in 10of the assurer's likely findings raised and fixed before fieldwork
target2daysto answer an assurer request, with the evidence already cited
In short

What is ESG Data Assurance Readiness?

ESG Data Assurance Readiness traces every reported ESG figure to its source evidence and controls for ISSA 5000 assurance. Seven agents trace each figure through five layers, test controls, re-perform samples, collect evidence and write the findings an assurer would likely raise. The ESG Controller decides each finding, approves verified fixes and signs readiness with Internal Audit before fieldwork.

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Updated

The problem

Why the assurer finds it before you do

From periods beginning on or after 15 December 2026, ISSA 5000 assurers look past the printed total to the reporting process, the systems and the controls behind each sustainability figure. They ask how a number was calculated, which system it came from, which control checked it and what evidence proves it. Most groups still prepare with spreadsheets and email, and the tie-out a week before publication stops at the workbook.

So the weak spots surface in fieldwork. A December estimate that was never replaced by the invoice, a monthly review done but never signed by the reviewer, evidence chased request by request across sites and owners. The findings arrive weeks before publication, when correcting a figure means a restated table under deadline, and a control without a signature cannot be relied on for the quarter.

typical75%of large companies already obtain assurance on some sustainability disclosures (IFAC, 2024 data)
typical15 Dec 2026ISSA 5000 applies to periods beginning on or after this date (IAASB)
Where the weeks before fieldwork go, in working daysestimated
By hand41 days
With the solution7.5 days
  • Tying each figure past the workbook to the system and the invoice10 → 1 d
  • Walking through controls and looking for reviewer sign-offs6 → 1 d
  • Picking samples and re-performing them against source documents5 → 0.5 d
  • Requesting, chasing and checking evidence from data owners12 → 3 d
  • Correcting figures after the assurer's findings8 → 2 d

Estimated split for preparing one year's sustainability statement for limited assurance, by hand and with the solution.

How it works

How a figure becomes ready

Seven agents trace, sample, test and write the findings an assurer would raise, and check each other; the ESG Controller decides and signs with Internal Audit.

What comes in
Sources in6 systems · statement, energy, ERP, HR, EHS, evidence library
Agents at work
Tracerfive layers
Then
Samplerre-performs
Control testerinspects instances
Then
Mock assurerlikely findings
Evidence collectorexact document
Then
Readiness scorermoves with each fix
Assurer liaisonreleased packs
A person decides
ESG Controllerdecides, signs with Internal Audit
What comes out
Traced figure
Signed readiness
Released evidence
One case, step by step

One weak figure, from overnight trace to signed readiness

Kestrel & Vane Group's FY2026 sustainability statement is in draft. Ashby Quill Assurance starts limited-assurance fieldwork in 21 days, applying ISSA 5000 early as agreed in the engagement letter. Here is Monday 1 February, screen by screen, in the working solution.

  1. 01Monday morning

    The agents worked overnight; she reads what they found

    Ingrid Svensson · ESG Controller

    Readiness is 87%: 127 of 146 figures ready, 14 weak, 5 gaps, up 3 points since 25 January against a target of 95% by 19 February. In the overnight thread the Tracer reports that it re-traced 41 figures on 6 statement pages and one changed: Scope 2 location-based, 48,210 tCO2e, is now weak at the source. Five items need her, from two new likely findings to an expired HR system connection.

    “Next: Scope 2 location-based is weak at the source. The agents traced it, re-checked 25 site-months and drafted two fixes.”

  2. 02One click

    The statement page, with the figure's X-ray beside it

    Ingrid Svensson · ESG Controller

    She works from page 41 as it will be published, E1-6 Gross Scopes 1, 2, 3 and total GHG emissions, with every figure marked Ready, Weak or Gap. Clicking 48,210 opens its five layers: the figure ties out, the Scope 2 workbook v7 re-computes, and the source system is the first weak layer. 741 of 744 site-months come from invoices or meter reads; three December values are estimates whose invoices arrived after the 10 January cut-off.

    Tracer · confidence 96% — read-only on every system, it never changes a reported figure.

  3. 03She asks

    “Which sites are estimated?” — answered with the sources

    Ingrid Svensson and the Tracer

    She asks under the figure, in plain words. The Tracer answers with the three sites and their numbers: Ostrava plant 1,840 MWh against an invoice of 2,112, Monterrey DC 1,210 against 1,166, Pune service centre 960 against 1,128. Each value carries a numbered citation that opens the passage it was read from. Above it, the Mock assurer's two proposed fixes wait for her decision.

    “All three invoices arrived after the 10 January cut-off.”

  4. 0402:10 – 02:24

    The overnight run, step by step

    The agents

    Run RN-0412 took 14 minutes. Each agent shows its plan, what it read, how sure it is and who it handed to. The Tracer read the statement, the workbook, the grid factor set and the three sites' energy records in 2 min 40 s, then handed the control and evidence layers to the Sampler and the Control tester.

    “Agents read only; people decide.”

  5. 0502:13

    25 site-months re-performed against supplier invoices

    Sampler

    From a population of 744 site-months and 117,450 MWh, the Sampler picked 22 items by MWh-weighted random selection and added the 3 estimates as targeted items, the sample size Ashby Quill used last year. The 22 agree within 1%. The 3 targeted items differ by +272, −44 and +168 MWh: +396 MWh, or +223 tCO2e, 0.46% of the figure.

    It reports every difference, however small, and never replaces the assurer's own sampling.

  6. 0602:16

    EN-C04: designed well, not signed in December

    Control tester

    EN-C04 says the regional reviewer signs each monthly meter and invoice review within 10 working days. The Control tester followed one site end to end, then inspected every Q4 instance: October and November are signed by Tomasz Wilk. For December the 62 site reviews were done, but no reviewer sign-off is recorded. Design effective; operating effectiveness deficient for December.

    Control tester · confidence 94% — it proposes the conclusion; Internal Audit confirms it.

  7. 0702:19

    The findings an ISSA 5000 assurer would likely raise

    Mock assurer

    F-01, a misstatement: December estimates at 3 sites were not replaced by invoices, +223 tCO2e, below performance materiality of 5% but a step the assurer will test. F-02, a control deficiency: EN-C04 has no reviewer sign-off for December. Each carries its basis, the figures it touches, its confidence and the likely outcome. Ingrid can accept, edit or dismiss each one with a reason.

    F-01: “Likely raised as a misstatement the assurer asks you to correct; not a modified conclusion.”

  8. 0809:18

    She accepts both findings and assigns two fixes

    Ingrid Svensson · ESG Controller

    X-9, replace the December estimates with invoices at Ostrava, Monterrey and Pune, goes to Mateo Lindqvist, due 5 February. X-10, record the December EN-C04 reviewer sign-off with evidence, goes to Tomasz Wilk, due 4 February. Before she confirms she sees what they are worth: 6 figures ready, readiness 87% → 91%. The Evidence collector notifies both owners.

    “The agents re-run the trace and the sample when each owner marks the fix done.”

  9. 09Nothing unseen

    Evidence goes to the assurer only when she releases it

    Ingrid Svensson and the Assurer liaison

    In the assurer room the Assurer liaison has assembled a pack for each of Ashby Quill's 18 requests: 12 released, AQ-07 waiting on X-9 and X-10. Ingrid previews AQ-11, water withdrawal by site with meter evidence: five documents, each read from its source and fingerprinted. She releases it to Ashby Quill read-only.

    “Read-only for the assurer · every view is logged.”

  10. 10Before fieldwork

    Two people sign readiness, with every exception on record

    Ingrid Svensson and Priya Raman

    The Readiness scorer checks the conditions: every likely finding accepted or dismissed, every figure in scope traced through five layers, and readiness at 95% or a reason code on each remaining exception. Nineteen figures are not yet ready, each with its finding and a fix due before 22 February. Once each has a reason code, Ingrid signs as ESG Controller and Priya Raman as Internal Audit Lead.

    Signature meaning: “Ready for limited assurance fieldwork, exceptions recorded.”

Who it’s for

Built for everyone who answers to the assurer.

The same statement, seen by four of the people who carry it into fieldwork — what the weeks before looked like, and what they look like now.

IS
Ingrid SvenssonESG Controller, Group Finance · decides, releases and signs
ESG Controller
Before
Owns the statement's controls and the relationship with the assurer, and hears about the weak figures in fieldwork, two weeks before publication.
Now
“I want to see the assurer's findings before the assurer does.” She opens each weak figure's layers, decides the likely findings, assigns fixes and approves them once the agents verify.
ML
Mateo LindqvistSustainability data owner, energy and emissions · 62 sites
Sustainability data owner
Before
Loads site energy data in January, with December often estimated, then answers evidence requests by email, one back-and-forth at a time.
Now
“Tell me exactly which invoice you need, for which site and month.” Each request names the document, site, period and due date, and a wrong file comes back with the reason.
PR
Priya RamanInternal Audit Lead · confirms control conclusions, co-signs
Internal Audit Lead
Before
Asked to give comfort on sustainability controls before fieldwork, with the evidence of each review in an email or a ticked spreadsheet.
Now
“A control without a reviewer's signature is a control that didn't run.” She sees each control tested on its real instances, confirms the conclusion and adds the second signature.
NF
Nadia FerreiraEngagement manager, Ashby Quill Assurance · read-only
External assurer
Before
Plans fieldwork from a list of requests, then waits days for each document and finds the gaps herself.
Now
“Show me the path from the 48,210 to the invoices.” She reads the packs released to her, each document cited to its source, and asks questions in one thread.
Built on the engine

7 agents. Each with one job, and hard limits.

Seven agents trace, sample, test and write the findings an assurer would raise, and check each other; the ESG Controller decides and signs with Internal Audit.

Tracer

Builds the path of every reported figure: statement, calculation, source system, control and evidence. It re-computes the workbook from its inputs, reads every input in its system of record and marks the first weak layer, with a confidence and the source passage for each.

  • Read-only on every system of record; never changes a reported figure
  • Every link cites its source passage
  • Below 80% confidence a person reviews
Control tester

Tests control design by walkthrough and operating effectiveness by inspecting real instances, the way an ISSA 5000 assurer would.

  • Never concludes a control is effective without the reviewer's evidence
  • Internal Audit confirms every conclusion
Sampler

Picks a risk-weighted sample from each figure's population and re-performs every item against its source document.

  • Reports every difference, however small
  • Never replaces the assurer's own sampling
Evidence collector

Asks each owner for the exact document, reminds them, and checks that what comes back is for the right site, period and amount.

  • Never accepts a document for the wrong period or site
  • Reminders go out only after a person presses Send
Mock assurer

Writes the findings an ISSA 5000 assurer would probably raise: the basis, the evidence, the effect against materiality and the likely outcome, with a drafted fix for each.

  • Never contacts the real assurer
  • States its confidence; below 80% a person reviews
  • The ESG Controller accepts or dismisses every finding
Readiness scorer

Computes readiness, explains every movement, projects the effect of each fix before anyone accepts it, and checks the sign-off conditions.

  • A figure is ready only when all five layers are strong and no finding is open
Assurer liaison

Assembles an evidence pack for each of the assurer's requests from cited sources, and drafts answers to the assurer's questions from the record.

  • Shares nothing until the ESG Controller releases it
  • The assurer's access is read-only
ESG Controller and Internal Audit

Decide and sign. The agents propose; a named person decides.

Ask in plain words

Ask about any figure, control or request, or tell the agents what to do

Ask in plain words on any screen. The agents answer with citations to the passage they read, and act on what you ask — nothing is sent without you.

Why is Scope 2 location-based weak?

The figure itself ties out: 48,210 tCO2e on page 41 matches the workbook. The weakness is the source: Ostrava, Monterrey and Pune kept a December estimate after the invoices arrived, and the invoices show 396 MWh more. That is +223 tCO2e (0.46%). December's EN-C04 review also has no reviewer sign-off.

What would Ashby Quill find if fieldwork started today?

The Mock assurer expects 10 findings: 3 misstatements, 3 control deficiencies, 2 evidence gaps and 2 method points. None is above performance materiality of 5% per metric. The largest is F-05: 4,500 tCO2e of credits with no retirement record. The most likely to change the conclusion's wording is F-04, the unapproved category 11 method.

Remind every owner with an overdue evidence request

Two requests are overdue: ER-0388 contractor hours (Ravi Shah, 3 days) and ER-0385 Halden HR export (Grace Mbeki, 2 days). I selected both and drafted the reminders. Press Send to send them; nothing goes out without you.

Draft our answer to Nadia's question on December estimates

Nadia asked how December estimates are replaced by actuals and who checks it. The close calendar says estimates are replaced before the statement is final, but three were not. I drafted a plain answer that says so, names fixes X-9 and X-10, and promises AQ-07 with all 25 sampled invoices. It is in the assurer room for you to edit and send.

Every screen

The working solution, as it ships.

13 screens from the working solution, on its sample data. Pick one to see it large.

TodayReadiness for assurance, what the agents found overnight in their own words, and the five things that need the ESG Controller.
Statement X-rayThe statement page as it will be published, every figure marked Ready, Weak or Gap, and the five layers of the selected figure with the first weak layer open.
Ask about a figureThe agents' conversation on one figure: what each found, the two fixes proposed for a decision, and a cited answer to a plain question.
Agent runsEvery run step by step: each agent's plan, the sources it read, its confidence, its result and who it handed to.
SamplesThe population, the method and the 25 items re-performed against supplier invoices, filtered to the three that differ.
Control testWhat the control says, how it was tested — walkthrough, instances, cross-check — and the conclusion for Internal Audit to confirm.
Likely findingsWhat an ISSA 5000 assurer would probably raise, with type, effect against materiality, confidence and likely outcome — each to accept, edit or dismiss.
Accept and assignTwo fixes with owner and due date, and the readiness they will move before anyone confirms.
Fixes before fieldworkEvery fix with the figures it makes ready; the ones the agents verified wait for approval, the overdue one is flagged.
Evidence requestsRequests with their clocks, and a returned document the Evidence collector caught as the wrong quarter, ready to go back with a reason.
Assurer roomThe assurer's requests and the evidence pack for each, every document cited and fingerprinted, released read-only.
Readiness sign-offThe conditions checked, the remaining exceptions each needing a reason code, and two signatures: ESG Controller and Internal Audit.
Audit trailEvery action by people and agents in order, with what it touched; it cannot be edited and exports for the assurer.
Governance

Built for assurance: cited, decided, signed, on the record.

Every value cites its sourceEvery layer, agent statement and finding links to the passage it came from — the statement page, the workbook cell, the system record, the invoice, the sign-off log — with who read it and when.
Read-only on every systemThe agents read the ERP, HR, energy, EHS, registry and evidence systems read-only. They never change a reported figure; they propose, and people decide.
A person decides every findingThe ESG Controller accepts, edits or dismisses each likely finding with a reason code. A fix is approved only after the agents have re-run the trace and the sample and verified it.
Two people sign readinessReadiness is signed by the ESG Controller and the Internal Audit Lead, each with the meaning of the signature recorded, and every remaining exception carries a reason code.
The assurer sees only what you releaseThe assurer works in a read-only room with the packs the Controller released. Every release and every view is logged.
Every step on the audit trailEvery action by people and agents is recorded in order with what it touched. The trail cannot be edited, threshold and rule changes are logged, and it exports for the assurer.
Configuration

Judged by your engagement letter, not ours

Materiality, sampling and the rules that mark a layer weak are settings. Saved changes apply from the next run and are logged.

SettingDefaultChoose from
Performance materiality per figure5%From the engagement letter; any value
Clearly trivial0.2%Differences below it are listed, not raised
Readiness target95%Sign-off without reason codes needs this
Agent confidence for a person to review80%Below it, a person reviews before it counts
Sample size per high-risk figure25 itemsLast year's assurer sample size, or your own
Framework and assurance levelESRS (CSRD) · limitedESRS (CSRD) · ISSB IFRS S1/S2 · GHG Protocol only — limited or reasonable
An estimate still used 20 days after period endSource layer is WeakOn · Off
A sample difference above clearly trivialOffOn: the Sampler widens the sample by 10 items · Off
Connections

Works with the systems your figures already come from

Statement and workbooksthe draft sustainability statement and its calculation workbooks
Energy and meter datameter reads, supplier invoices and estimates, by site and month
ERPspend cube, accruals and company codes for Scope 3
HR systemworkers, grades, pay and leavers
EHS systemincidents, hours worked and contractors
Evidence library and registryinvoices, logs, sign-offs, control register and credit retirements
What it changes

The difference, in numbers.

Every figure is labelled: a target the solution is built to, an estimate, a typical published result, or a proven one.

target
100%
of figures in assurance scope traced through five layers before fieldwork
146 figures
every layer opens its source
target
9 in 10
of the assurer's likely findings raised and fixed before fieldwork
Todayfound in fieldwork
Target≥ 9 in 10 found first
target
2days
to answer an assurer request, with the evidence already cited
Todayweeks of email
Target≤ 2 business days

“demo” = seen in the working solution, on its sample data · “target” = the design goal, measured in the live solution · “estimated” = our estimate · “typical” = published figures (IAASB, ISSA 5000 — effective for periods beginning on or after 15 December 2026; IFAC, State of Play in Sustainability Assurance, 2024 data — 75% of large companies obtain some assurance; Accountancy Europe CSRD practice forum, 2026 — sustainability controls less robust than financial reporting). People, companies, sites and systems named on this page are fictional — characters and sample data in the working solution.

Questions

What ESG controllers and internal auditors ask us.

What is ESG Data Assurance Readiness?

ESG Data Assurance Readiness traces every reported ESG figure to its source evidence and controls for ISSA 5000 assurance. Seven agents trace each figure through five layers, test controls, re-perform samples, collect evidence and write the findings an assurer would likely raise. The ESG Controller decides each finding, approves verified fixes and signs readiness with Internal Audit before fieldwork.

What does ISSA 5000 readiness mean for a sustainability statement?

ISSA 5000 applies to assurance on periods beginning on or after 15 December 2026, and its assurers look at the reporting process, systems and controls behind each figure, not only the printed total. Being ready means each figure in scope can be followed from the statement to its calculation, source system, control and evidence, with the weak points fixed before fieldwork starts.

How does it trace a figure back to source?

The Tracer finds the figure's calculation, re-computes it from its inputs, reads every input in its system of record read-only, and links the control and the evidence. Each of the five layers gets a status, a confidence and the source passage, and the first weak layer is marked — for example, three December site-months still on estimates.

Does it replace our assurer's testing?

No. The agents prepare you the way an assurer would test you. The Sampler never replaces the assurer's own sampling, and the Mock assurer never contacts the real assurer; it writes the findings it expects, with its confidence, for the ESG Controller to accept or dismiss.

What can the external assurer see?

Only the evidence packs the ESG Controller releases, read-only. The Assurer liaison assembles each pack from cited sources and drafts answers to the assurer's questions, which the Controller edits and sends. Every release and every view is logged.

Do people stay in control?

Yes. The agents read, draft and propose; they never approve. The ESG Controller accepts, edits or dismisses each finding with a reason code, approves a fix only after the agents verify it, and signs readiness with the Internal Audit Lead. Below 80% confidence, a person reviews before anything counts.

Which frameworks and assurance levels does it work with?

The scope is set in Settings: ESRS (CSRD), ISSB IFRS S1/S2 or GHG Protocol only, for limited or reasonable assurance. Performance materiality, clearly trivial, sample size and the readiness target come from your engagement letter and are settings too.

How long does it take to go live?

The Agentic Solution Engine builds and deploys it from your requirements and documents — your draft statement, calculation workbooks, control register and engagement letter — and it goes live once every quality gate has passed. We will walk you through it on your own statement first.

See it on
your statement.

We'll run ESG Data Assurance Readiness on your own draft statement, its workbooks and the systems behind them.