Why do major infrastructure projects cost so much and take so long?

Cost overruns and delays continue to challenge major infrastructure projects worldwide.

This places immense pressure on public balance sheets and reduces economic returns.

Declining public trust in government is also a key concern.

A new ICE green paper programme explores how global best practice in governance and assurance can help deliver projects more effectively.

Running until 11 July, the consultation invites decision-makers, infrastructure professionals, civil society groups, and others to share their insights.

The extent of the challenge

Research from Saïd Business School examined the gap between forecasts and outturns – the estimated and actual cost, time, and benefits – for 3,022 projects.

It found that only 27% remained on or under budget. Alarmingly, only 0.2% completed on time, within budget, and with expected benefits fully realised.

These inefficiencies are not unique to any one country. A McKinsey study of 500 global mega projects showed that only 5% completed within their original budget and schedule.

Unless the public sector improves major project delivery, the public will lose faith that they’ll get the infrastructure they need.

Investor confidence will also erode, making the private sector less likely to invest in critical projects.

With private capital fundamental to meeting governments’ infrastructure ambitions, this presents a significant challenge.

So, what’s the solution?

In the UK, the Infrastructure and Projects Authority – now superseded by the National Infrastructure and Service Transformation Authority (NISTA) – estimates that adopting best-practice delivery methods could reduce project overruns by up to 25%.

There is existing guidance, but it can be generic and subject to interpretation by project teams.

The ICE is interested in how improved governance and assurance can support the use of guidance and lessons learnt more consistently at a project level.

These frameworks aim to support accurate forecasting and effective delivery. But are they fit for purpose? Or are they adding unnecessary complexity that hampers innovation?

The consultation builds on previous ICE work, including a 2019 report on the gap between forecasts and outturns and the principles of the Project 13 enterprise model.

It also draws on the ICE’s recent recommendations for the UK's newly established delivery body, NISTA.

Next steps

The findings will inform an ICE policy paper later in 2025. This paper will offer options and solutions for policymakers to consider when advising on and delivering major infrastructure projects.

In an era of low trust in governments, delivering better outcomes for the public is crucial.

Accurate forecasting and efficient delivery of major projects will be important pieces of this puzzle.

Your input to this green paper will help the ICE understand how best-practice governance and assurance can help – and inform effective recommendations to policymakers worldwide.

Respond to the consultation