When should government use private finance to deliver infrastructure, and what conditions make it work?
Private finance — whether through PFI, PPP, or bespoke structures — can accelerate infrastructure delivery and transfer risk to parties better placed to manage it. It can also be expensive, inflexible, and poorly suited to projects where demand or technology risk is hard to price. The decision framework matters enormously.
This work distilled 12 key considerations from over 140 prior NAO reports — covering how government creates the right market conditions, makes effective financing decisions, and applies an appropriate commercial strategy for using private capital in infrastructure delivery. It is the most comprehensive synthesis of lessons from the UK's experience of private finance in infrastructure.
SDWH provides independent analysis of:
- Private finance decision frameworks; business case structure for capital projects
- Risk allocation options
- The conditions under which private finance has and has not delivered value in comparable programmes
How do government guarantees support private infrastructure investment, and what do they cost the taxpayer?
Government guarantees can unlock private investment in infrastructure that would otherwise not proceed — by reducing the financing cost for projects that meet certain eligibility criteria. But guarantees are contingent liabilities: the cost to the taxpayer is not zero, and the pricing and risk management of the guarantee portfolio matters. A call on a guarantee triggers an immediate cash cost for the guarantor to settle the guaranteed commitment, such as repaying a lender when the borrower has defaulted on a guaranteed loan.
The UK Guarantees Scheme managed a portfolio of £1.7bn in unconditional and irrevocable guarantees as part of a £40bn programme — and the NAO's assessment of this work was attributed with £1,372m of financial impact in the 2024–25 Annual Report. This work examined how guarantees were priced to satisfy state aid requirements, how credit risk was monitored, and what the tail-risk exposure implied for public finances.
SDWH provides independent analysis of:
- Guarantee framework structure and design options
- Contingent liability assessment approaches; pricing framework methodology
- Governance arrangements for government guarantee portfolios
How should government release public land to support housing delivery, and what does good value look like?
Government holds substantial land assets that could support new housing delivery. The decision about how to release that land — through joint ventures, direct sales, or development agreements — determines the proceeds achieved and the number of homes, business premises or infrastructure that will ultimately be constructed. These objectives are not always aligned.
This work examined the programme to release government land banks and found that, at the point of review, government was not systematically collecting data on either sale proceeds or housing delivery — making it impossible to assess value. The review prompted a change in approach.
SDWH provides independent analysis of:
- Land disposal strategy options; joint venture structuring approaches
- Value assessment frameworks
- The trade-offs between financial and policy objectives in asset disposal programmes
What are the real trade-offs between government borrowing and private finance for capital investment?
The choice between financing capital investment through government borrowing and using private finance involves trade-offs that can lead to misunderstanding on both sides. Private finance is not simply "off balance sheet" government borrowing, and government borrowing is not always cheaper when risk is properly accounted for.
This work provides a rigorous framework for comparing public and private financing alternatives, examining the contribution of private finance to infrastructure delivery and the conditions under which each approach delivers better value. It draws on the UK's extensive — and mixed — experience of both.
SDWH provides independent analysis of:
- Financing option appraisal methodology; Green Book alignment for major capital decisions
- The risk-adjusted cost comparison between public and private finance