Project complexity is ever growing and needs to be understood and measured better to assist modern project management. The overall ambition of this paper is therefore to define a measure of project complexity in order to assist decision-making. A synthesised literature review on existing complexity measures is proposed in order to highlight their limitations. Then, we identify the multiple aspects of project complexity. We then propose a multi-criteria approach to project complexity evaluation, through the use of the Analytic Hierarchy Process. In the end, it permits to define a relative project complexity measure. Complexity scales and subscales are defined in order to highlight the most complex alternatives and their principal sources of complexity within the set of criteria and sub-criteria which exist in the hierarchical structure. Finally, a case study within a start-up firm in the entertainment industry is performed. Conclusions and research perspectives are given in the end.

The management of large engineering projects is often a combination of the focus on planning and control, and the ambition to be flexible given the complexity and uncertainties that characterizes these kinds of projects. However, control and flexibility impose contradictory requirements upon the management of these projects. The literature on project management reflects this contradiction. Some authors underline that projects require firm planning and control, thus downplaying the role of flexibility. Others emphasis that projects require flexibility and responsiveness, thus moving away from rigid planning and control. In this contribution, we suggest that in practice project managers acknowledge the weakness of both extremes and therefore strive to combine the two. Moreover, we argue that project success is at risk when project managers do not succeed in meeting the requirements of control and flexibility. To be able to investigate how these competing requirements are dealt with in practice, a framework is developed. The usefulness of the framework is explored by applying the framework to the large engineering project Randstadrail—a light rail project in The Netherlands.