Over the past decades, Dutch infrastructure projects have been delivered through various procurement and delivery models, each aiming to address recurring challenges related to uncertainty, complexity and fragmentation. While traditional and integrated contract forms have offered specific advantages, they have also been associated with persistent drawbacks, including high failure costs, increasingly adversarial client–contractor relationships, and a declining willingness of market parties to participate in projects. In response, public clients have increasingly explored alternative approaches to organising project delivery. One such approach is the two-phase procurement model, which seeks to involve contractor expertise earlier in the project lifecycle to improve predictability and risk management.

Despite its growing application, the two-phase procurement approach is not evaluated uniformly in practice. Stakeholders differ in how they interpret its core mechanisms and assess its outcomes. This study therefore analyses how stakeholders in Dutch infrastructure projects perceive and evaluate the two-phase procurement approach in relation to its intended objectives, with specific attention to how trade-offs are prioritised in practice.

The two-phase procurement approach can be positioned as a form of Early Contractor Involvement (ECI). Contractors are selected at an early stage primarily on qualitative criteria, after which design development and cost elaboration take place jointly in Phase 1. A formal Go/No-Go decision then determines whether the project proceeds to execution in Phase 2 under agreed conditions and a final price.

Using Q-methodology, this study identifies shared stakeholder perspectives based on the ranking of statements and subsequent factor analysis. Eight themes derived from the ECI literature guided the analysis: Capability, Collaboration, Culture, Innovation, Pricing, Risk Allocation, Transaction Costs, and Value for Money. The analysis reveals three distinct perspectives on the two-phase procurement approach.

Across these perspectives, there is broad consensus that the approach shifts key discussions on feasibility, risk, design and cost to an earlier stage. This is associated with reduced fragmentation between design and execution, improved buildability and more stable execution. Costs tend to increase during Phase 1 but remain more predictable during Phase 2, while transaction costs are redistributed rather than reduced. The perspectives diverge in how these effects are valued, particularly with regard to transparency, public client capability and bargaining power.
Overall, the study concludes that the two-phase procurement approach can enhance predictability and collaboration, but only under demanding conditions. Its effectiveness depends less on the model itself than on the capability and responsibility of both public clients and contractors in its application.