A mixed-methods comparison of the performance of Dutch PPP and non-PPP infrastructure projects

Rijkswaterstaat, the Netherlands' major procurer of transport infrastructure, uses two primary contract types: Design and Construct (D&C) and Design-Build-Finance-Maintain (DBFM). In this chapter, we comparatively analyze the cost and time performance of these contract types using quantitative financial data on DBFM (N=12) and large D&C projects (N=18), a survey among public and private managers involved in these projects (N=163), and interviews with public and private managers as well as financiers involved in the DBFM projects (N=34). We find that DBFM projects perform significantly better than D&C projects on time performance. For cost performance, the public sector perceives DBFM projects to perform better, but this is not the case from the private sector perspective. This raises questions regarding the sustainability of this contract type. Respondents emphasize the need for intense collaboration and the use of relational governance mechanisms to maintain the performance advantage of DBFM.