Topic 2.5 — Business Cases and Value for Money

Why this matters in public value

Every public manager who has taken a spending proposal to a finance committee, a council, or a board has felt the moment when a sound idea meets a question the spreadsheet cannot answer: is this the right thing for us to be doing, and can you prove it before we commit? A private investment case can settle for a positive net present value and a board's appetite for risk. A public one cannot, because the money is not the organization's own in the same sense, and the people who will judge the decision — voters, service users, auditors, the media — were never asked to buy shares.

That gap is why well-intentioned public spending decisions so often unravel after approval rather than before it. A programme sails through an economic appraisal showing a strong benefit-cost ratio, then stalls because no one worked out how it would be procured, the delivery organization never had the staff to run it, or an authorizer who was never consulted objects once the spend becomes public. Topic 1.2 — The Strategic Triangle: Legitimacy, Value, and Capacity sets out why legitimacy, value, and capacity all have to hold together (see Topic 1.2 — The Strategic Triangle: Legitimacy, Value, and Capacity); this topic is about the instrument — the business case — that public bodies use to test all three before money moves, and the audit machinery that checks, afterwards, whether the test was honest.

The stakes show up twice: when a weak business case waves through a bad decision, and when a business case is so heavy and procedural that it becomes a barrier to anything happening at all. Getting this right is not a compliance exercise bolted onto the real work of public management — it is one of the few moments where legitimacy, value, and deliverability are forced into the same document, in front of the same decision-maker, at once.

Core concepts

A business case sets out the reasoning for a proposed spend: the problem it solves, the options considered, the costs and benefits, and how the money would be spent, so a decision-maker can approve, reject, or send it back. A private-sector business case mainly secures internal capital against competing uses inside one firm. A public one has to do more: survive scrutiny from people who never agreed, by buying a product, that the spend was worth it.

The five case model is the dominant public-sector pattern for this reasoning, developed in UK central government and adopted, in close variants, elsewhere — New Zealand's Treasury built its 'Better Business Cases' guidance on the same structure with the UK Treasury. It requires five distinct cases rather than one: strategic (is this the right thing to do), economic (does it offer value for money among the options), commercial (can it be procured on terms the market will accept), financial (can the organization afford it), and management (can it be delivered, governed, and its benefits tracked). Separating the five matters because a proposal can fail on any one even while succeeding on the others — an excellent use of money can still be un-procurable, unaffordable this year, or beyond the organization's management capacity.

The strategic case answers a narrower question than it sounds: not 'is this valuable' but 'is this the right problem, in line with our objectives, with a genuine case for change rather than a preference already made'. Written after a preferred solution is chosen, it tends to read backwards, listing objectives that happen to match the solution instead of testing whether the solution follows from them.

The economic case is where formal appraisal does its work: a genuine long-list of options narrowed to a short-list, each tested against a realistic 'reference case' or 'do-minimum' counterfactual, using social cost–benefit or cost-effectiveness analysis on a common basis (see Topic 2.2 — Social Cost-Benefit and Cost-Effectiveness Analysis). Public appraisal typically uses a social discount rate — reflecting society's time preference and the opportunity cost of public capital — rather than a private firm's cost of capital, and counts costs and benefits falling on people outside the transaction. Net present value and benefit-cost ratios still appear, but as one input among several, not the entire test.

Optimism bias is the well-evidenced, systematic tendency to underestimate costs, timescales, and risks and overestimate benefits; a rigorous economic case adjusts for it explicitly, with an evidence-based uplift drawn from the outturn record of comparable past projects, rather than an informal contingency line. Unchecked optimism bias is one of the best-documented causes of public cost overrun on infrastructure, and several jurisdictions now require a stated, quantified adjustment for it.

The commercial, financial, and management cases are where a business case stops being an appraisal and starts being an operating plan. The commercial case tests the procurement route and market appetite, feeding directly into Topic 3.7 — Public Procurement and Commissioning (see Topic 3.7 — Public Procurement and Commissioning). The financial case tests affordability against the actual budget and funding profile — a different question from whether the spend is a good idea. The management case sets out governance, delivery risk, and a benefits realization plan naming who owns each expected benefit, since an unowned benefit is rarely realized.

Value for money, as public auditors use the term, is distinct from the economic case, though related. It is usually defined around three criteria, the 'three Es': economy (the right-quality inputs at lowest reasonable cost — spending less), efficiency (the most output from a given input — spending well), and effectiveness (achieving the intended outcomes — spending wisely). Some frameworks add a fourth 'E', equity, since a programme can be economical, efficient, and effective on average while distributing its costs and benefits unfairly. Value for money is assessed twice: prospectively, inside the economic case, and retrospectively, by an independent audit body — and that difference matters throughout this topic.

Value-for-money audit, sometimes called performance audit, is the after-the-fact, independent examination of whether spending actually achieved economy, efficiency, and effectiveness, conducted by a body separate from the one that approved or delivered it. Institutions such as the United Kingdom's National Audit Office and the United States' Government Accountability Office report to a legislature rather than the spending department, which is what gives a performance audit its independence. The business case is the ex ante test; the value-for-money audit is the ex post check on whether that test was honest and the spend delivered what it promised.

How a public business case differs from a private investment case runs through all of the above. A private investment case satisfies one leg of the triangle (see Topic 1.2 — The Strategic Triangle: Legitimacy, Value, and Capacity) in miniature — capacity and a value proposition validated by return on capital — because legitimacy to spend is already settled by ownership. A public business case must satisfy the legitimacy leg explicitly: defensible to an authorizing environment that never bought a share, and accountable for value falling on people who are not the immediate purchaser, using money that was raised, not earned in a market transaction. A positive net present value is necessary but never sufficient; a business case that cannot answer 'would our authorizers, and the people affected, sanction this' has not finished its job, however strong its arithmetic.

Best practices

Start with the strategic case, not the spreadsheet. Establish the problem and the case for change in plain language before quantifying anything, so the appraisal tests a genuine question rather than justifying a solution already preferred.
Build a real long-list of options and narrow it transparently. A short-list of one preferred option dressed up as several alternatives fails the economic case's basic purpose, which is comparison, not confirmation.
Use a credible reference case, not a straw man. Set the 'do-minimum' counterfactual at what would genuinely happen without the spend, since an artificially bleak baseline makes every option look better than it is.
Apply the social discount rate and distributional considerations consistently, drawing on the method in Topic 2.2 — Social Cost-Benefit and Cost-Effectiveness Analysis. Do not let a public appraisal quietly import a private discount rate or ignore who bears the costs and who gets the benefits (see Topic 2.2 — Social Cost-Benefit and Cost-Effectiveness Analysis).
Adjust explicitly for optimism bias, using evidence from comparable past projects. A stated, calculated uplift is defensible under scrutiny; an unstated contingency line invites the finding that costs were known to be underestimated.
Develop the commercial, financial, and management cases alongside the economic case, not after it. A programme strong only on paper in the economic case tends to fail at delivery, not at approval.
Name an owner for every expected benefit before approval, not after. A benefits realization plan without a named, accountable owner rarely survives the next budget cycle's competing priorities.
Route major spend through an independent assurance gate before commitment. A review team separate from the sponsoring programme, empowered to say no, catches optimism and scope creep an internal sign-off chain is unlikely to challenge.
Keep value-for-money audit independent of the approval chain, in both timing and reporting line. An audit reporting to the body that approved the spend is marking its own homework, whatever its formal remit says.
Report economy, efficiency, and effectiveness as separate findings, not one blended score. A programme can be economical and ineffective, or effective and poor value for money, and collapsing the three hides the distinction a decision-maker needs.
Revisit the business case at each major decision point, not only at initial approval. A strategic outline case, an outline business case, and a full business case are meant to be successive tests as more is known, not stages that merely rubber-stamp an earlier approval.
Publish enough of the business case for the authorizing environment to actually scrutinize it. A business case that never leaves the finance function cannot do the legitimacy work Topic 1.2 — The Strategic Triangle: Legitimacy, Value, and Capacity — describes, however rigorous its arithmetic.

Questions to discuss with your team

Does our business case template genuinely force a strategic case, or does it let a pre-chosen solution walk straight through to the numbers? Many organizations have a template with a strategic-case section that is filled in last, after the preferred option is already agreed, which produces objectives written to match the answer rather than to test it. Use this question to pull three recent business cases and check whether the strategic case could plausibly have led to a different preferred option, or whether it was always going to land on the same one. Discuss what would change if the strategic case had to be signed off before any option appraisal began. This is not an accusation that every case is written backwards, only a prompt to check.

How do we currently correct for optimism bias, and have we ever checked our appraisals against what actually happened? Most organizations apply some form of contingency, but far fewer track whether their past projects' actual costs and benefits matched what the business case predicted. Optimism bias is well documented and broadly predictable in direction, which is exactly what makes it correctable if an organization is honest about its own track record. Use this question to find two or three completed major spends and compare predicted to outturn figures, however roughly. Discuss whether the gap, if there is one, is being fed back into how the next business case is appraised, or whether each new case starts from the same optimistic assumptions as the last.

Who audits value for money in our organization, and are they independent of whoever approved the spend? Independence is what makes a value-for-money audit worth having; a review reporting to whoever signed off the original business case is a courtesy, not an audit. National audit institutions earn their credibility precisely by reporting to a legislature rather than to the executive whose spending they examine, and an internal equivalent needs the same separation to mean anything. Use this question to map who conducts value-for-money review here, on what, and to whom they report. Discuss whether that arrangement would survive being described plainly to an outsider, and what genuine independence would take.

Where in our approval process would a legitimacy failure show up before the money is committed, rather than after? The 'deliverable but unauthorized' pattern from Topic 1.2 — The Strategic Triangle: Legitimacy, Value, and Capacity shows up here as a proposal that sails through the economic and financial cases while the people who must consent have not been properly engaged. Use this question to identify who, in the current pipeline, would raise a legitimacy objection, and at what stage. Discuss whether that person sees the business case early enough to matter, or only once change is politically expensive.

Do the commercial, financial, and management cases get the same rigour as the economic case, or does the spreadsheet dominate the room? Appraisal skill commonly concentrates almost entirely on the economic case, leaving the other three thin or completed as a formality. This is understandable, since the economic case has the clearest professional discipline and the most obvious numbers to defend, but it is also how programmes with a strong net present value fail at delivery for reasons the business case never seriously tested. Use this question to pick a recent approved business case and honestly rate the depth of each of the five cases. Discuss which weaker case has caused the most trouble at delivery, and whether the pattern repeats elsewhere.

When did we last cancel or substantially change a programme because a later-stage business case update showed the numbers had moved? A business case used as a live test, not a one-off gate, should sometimes produce a 'no' or a 'not like this' at the outline or full-case stage. If no example comes to mind readily, that is itself informative about how the process actually functions here. Use this question to find an example, or notice if none exists. Discuss what that absence suggests about whether later-stage cases genuinely re-test the decision or merely document a commitment no longer being questioned.

In practice: a public value example

A regional public health authority — fictional, illustrative of a recurring pattern rather than a report on any real body — needed to decide how to expand diagnostic imaging capacity across a catchment area where waiting times for scans had grown for three years. Two options reached the short-list: a single large diagnostics hub attached to the main hospital, or three smaller satellite units placed in underserved towns.

The strategic case was strong for both options: reducing wait times and improving access were uncontested objectives, backed by patient survey data and referral statistics showing genuine unmet demand. The economic case favoured the single hub decisively: economies of scale in equipment and staffing gave it a materially higher benefit-cost ratio than the three satellite units, even after an optimism-bias uplift on construction costs drawn from the authority's two most recent capital projects. On the numbers alone, the hub was the clear choice, and the appraisal team recommended it.

The commercial and financial cases were worked through without major difficulty — the hub could be procured through an existing framework contract, and the capital cost fit the authority's funding envelope. It was the management case that exposed what the economic case had not captured: delivering the hub depended on recruiting specialist radiography staff who, the workforce plan showed, were not available in the numbers required, and would have been drawn from the very towns the satellite option would have served — towns whose councillors were already asking, publicly, why patients there would still travel further than before.

Rather than proceed on the economic case's arithmetic alone, the board sent the business case back for a hybrid option: a smaller central hub with two satellite units, phased so recruitment could keep pace with each opening. The revised economic case showed a lower benefit-cost ratio, but the management case was now credible, and the councillors were engaged before formal approval, not after. Three years later, an independent value-for-money audit found that the phased option had delivered slower initial wait-time improvement than the hub-only case had promised, but had avoided a workforce shortfall that would otherwise have delayed opening by well over a year. The audit's conclusion was not that the original economic case had been wrong on its own terms, but that a business case tested on the economic case alone would have approved a plan the authority could not actually have delivered on schedule.

Four sector lenses

Local government

Local authorities typically run a lighter version of the five-case model below major capital thresholds, so a large share of local spending never receives the full strategic-to-management treatment a national infrastructure programme would. This is often proportionate to genuinely smaller sums, but it also means a separate commercial and management case is most likely skipped exactly where local delivery capacity is thinnest. Local value-for-money scrutiny usually comes from internal audit, external auditors under a national local-audit regime, and, in many countries, direct challenge at open council meetings — real-time authorizing-environment pressure national programmes rarely face in the same way.

National government

National government is typically where the five-case model is most developed, with dedicated appraisal, commercial, and assurance functions and formal gateway reviews for major programmes. The risk here is the opposite of local government's: a heavily resourced economic case can grow so sophisticated it dominates the conversation, while the strategic case is quietly assumed rather than tested, because a well-funded department can make almost any proposal look appraised even when the underlying case for change is thin. National value-for-money audit, carried out by a supreme audit institution reporting to the legislature, is usually the most independent of the four lenses here, precisely because it sits outside the executive that approved the spend.

Nonprofits rarely face a mandated business-case template, but funders increasingly require something functionally similar before releasing money, and the five-case structure translates reasonably well even without the name. The financial case is often hardest for a nonprofit, since funding is commonly project-restricted, time-limited, and drawn from multiple donors with different reporting rules, making 'can we afford it over time' harder to answer than for a body with a stable tax base. Value for money is also contested in a specific way here: a funder's economy criterion (less spent per unit of activity) can sit in real tension with a mission-driven effectiveness criterion (reaching the hardest-to-serve people, who cost more to reach), a trade-off Topic 3.8 — Social Sector and Nonprofit Management explores from the funding-model side.

Multilateral and international

Multilateral bodies use their own project appraisal instruments — broadly analogous to a business case — that must satisfy a governing board representing many sovereign member states rather than one legislature, making the legitimacy leg more formal (a documented board approval) and less settled (board approval does not automatically confer legitimacy among the population where the project is delivered). Value-for-money audit here is often carried out by an independent evaluation function reporting to the governing board rather than to management, mirroring the separation national supreme audit institutions provide domestically. The economic case is complicated by genuinely divergent interests among donor states, recipient states, and affected communities — the plural-value problem this book returns to repeatedly (see Topic 1.4 — Public Goods, Merit Goods, and Value Pluralism).

Common failure modes

The solution-led business case. A preferred option is chosen first, informally, and the strategic and economic cases are written afterwards to justify it, producing a document that reads as rigorous while never having genuinely tested an alternative. The cost is usually invisible until a later value-for-money audit or a change of leadership asks why the short-list options were never real contenders.

Uncorrected optimism bias. Costs, timescales, and benefits are estimated without an evidence-based adjustment for the well-documented tendency to be too optimistic, leaving a contingency line as the only defence against reality. The cost lands as a cost or schedule overrun that could have been anticipated, since the pattern is predictable even when any individual project's overrun feels like bad luck.

A strong economic case propped up by four weak ones. The spreadsheet shows a clearly positive net present value, and the commercial, financial, and management cases are completed as a formality rather than genuinely worked through. The programme is approved on the strength of one case out of five, and fails at delivery on a dimension the appraisal never seriously tested.

Value-for-money audit without independence. The body reviewing whether money was well spent reports, directly or indirectly, to the body that spent it, so findings that would embarrass the sponsor are softened or never surface. This costs the organization the single most useful signal it has for correcting future business cases, since a captured audit function tells leadership what it already believes.

Approval treated as a single event rather than a staged test. A business case is approved once, at the strategic or outline stage, and subsequent full-business-case updates are treated as paperwork rather than a genuine re-test as costs, markets, and evidence change. The cost is a programme that continues past the point where an honest re-appraisal would have stopped or reshaped it, because no one with authority ever asked the question again.

Maturity model

Sub-dimension	Initiate	Develop	Standardize	Manage	Orchestrate
Strategic case is genuinely tested	Assumed from the sponsor's framing, rarely questioned	Written, but usually after a solution is already chosen	A mandatory, reviewed strategic case precedes any option appraisal	Strategic cases audited for whether options were genuinely open	Strategic case-making shared with affected communities before options are fixed
Economic case applies appraisal method consistently	Ad hoc, informal comparison of options	Cost–benefit or cost-effectiveness analysis used for large spends only	A standard method, discount rate, and optimism-bias adjustment applied organization-wide	Outturn costs and benefits tracked against appraisal and fed back	Appraisal method and assumptions benchmarked and shared across peer organizations
Commercial, financial, and management cases are developed in parallel	Completed late, as a formality, after the economic case is agreed	Developed for flagship programmes only	Mandatory for all major spend, resourced alongside the economic case	Weaknesses in any of the three trigger a hold on approval	Delivery capacity and market engagement shape the strategic case itself, not just later stages
Value-for-money audit is independent and acted upon	No routine independent review	Internal audit reviews some spend, reporting to management	An independent function with its own reporting line exists	Findings tracked to closure with public reporting	Audit findings systematically reshape future business-case guidance
Benefits are tracked after approval	Assumed to occur once delivery is complete	Tracked informally by the delivery team	A named benefits owner and tracking plan required for every approval	Benefit realization reported against the original business case	Under-realized benefits trigger organization-wide learning, not just project-level correction

Checklist

Write the strategic case and have it reviewed before any option appraisal begins.
Build a genuine long-list of options and document why each was included or excluded.
Set a credible reference case ('do-minimum') as the counterfactual for appraisal.
Apply a consistent social discount rate and distributional treatment, per the method in Topic 2.2 — Social Cost-Benefit and Cost-Effectiveness Analysis.
Apply an evidence-based optimism-bias uplift to costs, timescales, and benefits.
Develop the commercial, financial, and management cases alongside the economic case, not after it.
Name an accountable owner for every benefit claimed in the business case.
Route the business case through an assurance or gateway review independent of the sponsor.
Confirm the body conducting value-for-money audit reports independently of the approval chain.
Report economy, efficiency, and effectiveness as separate findings, not a single blended score.
Re-test the business case at each major decision stage, not only at initial approval.
Publish enough of the business case for the authorizing environment to scrutinize it.

Key sources

HM Treasury, The Green Book: Central Government Guidance on Appraisal and Evaluation — the foundational UK appraisal guidance underlying the economic case and its wider business-case guidance for programmes and projects.
New Zealand Treasury, Better Business Cases guidance — a five-case-model framework developed jointly with UK Treasury and adapted for New Zealand's public sector.
UK National Audit Office, value-for-money work — methodology and published reports defining and applying economy, efficiency, and effectiveness.
US Government Accountability Office, performance audit work — the US analogue to value-for-money audit, reporting to Congress.
OECD, Recommendation on Effective Public Investment Across Levels of Government and its accompanying toolkit — international principles for public investment governance.

References

Business case — Wikipedia — https://en.wikipedia.org/wiki/Business_case
HM Treasury — Wikipedia — https://en.wikipedia.org/wiki/HM_Treasury
Value for money — Wikipedia — https://en.wikipedia.org/wiki/Value_for_money
National Audit Office (United Kingdom) — Wikipedia — https://en.wikipedia.org/wiki/National_Audit_Office_(United_Kingdom)
Government Accountability Office — Wikipedia — https://en.wikipedia.org/wiki/Government_Accountability_Office
Performance audit — Wikipedia — https://en.wikipedia.org/wiki/Performance_audit
Net present value — Wikipedia — https://en.wikipedia.org/wiki/Net_present_value
Optimism bias — Wikipedia — https://en.wikipedia.org/wiki/Optimism_bias
Cost overrun — Wikipedia — https://en.wikipedia.org/wiki/Cost_overrun
Cost–benefit analysis — Wikipedia — https://en.wikipedia.org/wiki/Cost%E2%80%93benefit_analysis
OECD — Wikipedia — https://en.wikipedia.org/wiki/OECD
The Green Book: Central Government Guidance on Appraisal and Evaluation — HM Treasury / UK Government — https://www.gov.uk/government/publications/the-green-book-appraisal-and-evaluation-in-central-government
Value for money — National Audit Office (UK) — https://www.nao.org.uk/about-us/our-work/value-for-money-programme/
Better Business Cases — The Treasury, New Zealand — https://www.treasury.govt.nz/information-and-services/public-sector-leadership/investment-management/better-business-cases
What GAO Does — US Government Accountability Office — https://www.gao.gov/about/what-gao-does
OECD Recommendation on Effective Public Investment Across Levels of Government — OECD Legal Instruments — https://legalinstruments.oecd.org/en/instruments/OECD-LEGAL-0402