Public Infrastructure Buyer Maturity and Effective Use of Delivery Models

Public infrastructure systems face increasing pressure to deliver projects efficiently while managing fiscal, environmental, and political constraints. The effectiveness of delivery models—from Design–Bid–Build (DBB) and Design–Build (DB) to Early Contractor Involvement (ECI)—depends critically on the maturity of the public infrastructure buyer, including its capabilities, organisational design, and ability to engage with private partners. Drawing on consultations with the Network of Professionals in Infrastructure Delivery (IPP-P), this OECD expert conference will explore how public buyer maturity shapes delivery-model choice, risk allocation, and performance outcomes.

The conference will bring together academics, senior public buyers, and policy practitioners for an evidence-informed exchange. Discussions will focus on core buyer capabilities under different delivery models, short- and long-term constraints on feasible choices, and how insights from practice and research can be systematically applied. Designed as a fact-finding and bridge-building exercise, the event offers participants a structured forum to connect theory, empirical evidence, and practical experience, advancing a more coherent understanding of public infrastructure buyer maturity.

Discussions on public-sector “client maturity” are widespread in infrastructure policy and practice, yet they remain fragmented across communities:

• On the one hand, supply chain management (SCM) and operations research literatures—largely developed outside the public infrastructure domain—offer rich conceptual tools to understand coordination, risk, uncertainty, and system performance.
• On the other hand, insights into public buyer capability—particularly in relation to delivery-model choice—are often experiential, derived from practitioner interviews, case studies, and institutional memory, with limited formalisation or empirical testing.
• Economic theory provides some foundational anchors—especially around risk allocation, asset specificity, frequency, and hold-up problems—yet these insights are rarely translated into operational guidance for public buyers at portfolio or system level.

As a result, academics working on SCM, economists analysing procurement and contracting, and senior infrastructure practitioners often speak past one another, despite addressing closely related problems.The conference will bring together academics, senior public buyers, and policy practitioners for an evidence-informed exchange. Discussions will focus on core buyer capabilities under different delivery models, short- and long-term constraints on feasible choices, and how insights from practice and research can be systematically applied. Designed as a fact-finding and bridge-building exercise, the event offers participants a structured forum to connect theory, empirical evidence, and practical experience, advancing a more coherent understanding of public infrastructure buyer maturity.

The conference will centre on a simple but under-explored question: What capabilities must a public infrastructure buyer possess in order to engage effectively with different delivery models—and how do these capabilities shape make-or-buy decisions, risk allocation, and performance outcomes?

Discussions will focus on:

• Core public-buyer capabilities required under DBB (price-based), DB (greater risk-transfer), and ECI (collaborative delivery models).
•  How short-term capability constraints limit feasible delivery options, and how long-term capability development can expand them.
• The role of buyer maturity in managing uncertainty, supplier dependence, and post-contract adaptation.
• How experiential insights from practice can be systematically structured, compared, and tested.
• What can realistically be learned from SCM research—and where public infrastructure presents fundamentally different challenges.

The OECD’s work in this area builds on economic principles embedded in tools such as STEPS, which analyse procurement strategy, risk allocation, and capability needs at project level, with applications also to the portfolio. However, consultations with IPP-P members highlight the absence of system-level frameworks that link delivery-model choice, buyer maturity, and supply-chain conditions across portfolios and sectors.

This conference is intended as a fact-finding and bridge-building exercise—not to impose a single model, but to clarify concepts, surface evidence gaps, and identify promising directions for future OECD analytical work.

The conference brings together:

•  Academics working on SCM, procurement economics, infrastructure delivery, and organisational capability;
•  Senior public infrastructure buyers and delivery agencies;
• Policy practitioners involved in procurement reform and institutional design.

By convening these perspectives, the OECD aims to advance a more coherent and evidence-informed understanding of public infrastructure buyer maturity as a determinant of delivery success.