Solid evidence supporting the infrastructure investment narrative is still missing, and full-fledged investment solutions demonstrating the benefits of infrastructure investment for institutional investors remain elusive.

In this paper, we discuss the need, and propose an approach to benchmark long-term investments in infrastructure, where long-term investment simply refers to any unlisted and illiquid asset. We first highlight the reasons why benchmarking long-term infrastructure investments has become essential to match the supply and demand of long-term capital, improve asset allocation outcomes for investors and support the development of the economy. We then propose a roadmap detailing the steps to create benchmarks of long-term infrastructure investments.