Background
Infrastructure projects are among the most complex undertakings in both the public and private sectors. They require significant capital investment, unfold over long timelines, and are shaped by a high degree of uncertainty and risk (Harty et al., 2014). At the centre of these projects lies procurement—the process by which goods, services, and works are acquired (New Zealand Government Procurement, 2025). More than a transactional mechanism, procurement is a strategic function that directly influences how risk is distributed, how effectively projects are delivered, and how sustainable their long-term outcomes will be.
This research starts from the premise that not all procurement methodologies are equally effective in managing and allocating risk, particularly in large-scale infrastructure delivery. Evidence shows that certain models can unintentionally misallocate risk, resulting in inefficiencies, disputes, cost overruns, and underperformance (Flyvbjerg et al., 2004).
Accordingly, this study explores the comparative performance of procurement practices in infrastructure projects, with a particular focus on how different methodologies shape risk allocation, benefits realisation, and project outcomes. International research, including studies from the United Kingdom and Australia, demonstrates that procurement strategies play a decisive role in achieving value for money, effective risk management, and alignment with service delivery expectations. In both vertical and horizontal infrastructure delivery, the choice of procurement model significantly affects how risks are allocated and how responsibilities are shared and integrated among stakeholders (Regan et al., 2015).
By examining these dynamics, this research aims to contribute to a deeper understanding of procurement’s role in infrastructure success. It also evaluates the New Zealand context, assessing how local approaches to procurement and risk allocation compare with global best practices, and how they might be adapted to deliver more resilient, collaborative, and value-driven project outcomes.
Principle 1: Relational or Transactional
Procurements can be divided into relational and transactional approaches. Relational procurement emphasises collaboration, mutual trust, open communication, and shared problem-solving between buyer and seller. This is typical in models such as Alliances and Early Contractor Involvement (ECI). Transactional procurement, by contrast, is defined by standardised or bespoke contracts with limited engagement or feedback from the contractor, exemplified by traditional Design-Bid-Build (DBB) models.
