This thesis investigates how value is co-created and perceived between public clients and consultants during the front-end stages of infrastructure projects, where early decisions critically shape long-term outcomes. Drawing on a qualitative multi-case study of two Dutch infrastructure projects, the research identifies key resources, co-creation processes, and value outcomes generated. In addition, the study also emphasizes the role of human-centric and contextual factors, such as strategic priorities and structured service approaches, in influencing decision-making quality. The study offers practical recommendations which include early market engagement, iterative knowledge development, and co-created reporting frameworks to enhance collaboration and reduce delays. The visual framework developed serves as a reference for project managers to evaluate the effectiveness of co-creation process and improve value delivery in complex infrastructure projects.

One of the reasons for the failure of large infrastructure projects is the increasing complexity of such projects. Complexity is considered a source of risks. These risks can be negative, called threats, or positive, called opportunities. The current risk management process implemented in practice mainly deals with threats, and opportunities are almost not considered. This research aims to study how individuals involved in complex infrastructure projects can better set the scene for opportunity management and capitalize on the opportunities that complexities offer. First, a literature study was conducted to define the relevant concepts such as project complexity and opportunity management. Next, to understand the current approach of identifying opportunities in practice, interviews with practitioners in the field of infrastructure were conducted. After that, the aim was to study the possibility of exploiting complexities. This was achieved by organizing a workshop session, where four Project Managers collaborated to identify opportunities, in four infrastructure projects, that result from the technical (T), organizational (O) and external (E) complexity elements of the TOE framework developed by Bosch-Rekveldt et al. (2011). As a result, a technique that aims particularly at identifying the opportunities that emerge from the complexities was developed: the Complexity-Driven Opportunity Identification Technique (CDOIT). Finally, this technique was integrated in a roadmap that aims for the effective implementation of opportunity management in complex infrastructure projects. This study suggests having a common understanding among the project team of the concept of opportunity as a positive risk and how it is linked to the project objectives. These objectives should be clearly stated from the beginning of the project. Also, if the team is determined to identify and manage opportunities, and even more, the opportunities that result from the complexity of the project, this should be clear from the start and included in the risk management plan (RMP). Another important factor is to determine the people who should be involved in identifying opportunities. Furthermore, the techniques that can facilitate the identification of opportunities and how these will be assessed, handled and monitored should be determined. Also, individuals looking for opportunities should be equipped with the right positive mindset. This will help in switching from a threat-focused mindset to a mindset that focuses on the positive side of risk. This study also proposed five possibilities into how complexities can be exploited. This can be done using internal strengths, taking advantage of external weaknesses combined with internal strengths, aiming to turn internal weaknesses to strengths, through a better use of available resources, and by increasing the scope of the project.