AbstractIn today’s construction projects, which are getting more complex as a consequence of especially technical, organizational, and external aspects, complexities are considered a major source of risks. Moreover, risks may turn to complexity-creating elements and propagate additional risks through a bidirectional interaction. Complex construction projects, typically large-scale dynamic endeavors, require the realization of a high number of interdependent tasks through the consumption of various resources such as time, money, labor, and materials. In such projects, while complexities are usually assumed to be given or embedded, due to the subjective and dynamic characteristics of complexities, a tailored approach is required in order to manage them holistically without ignoring their interactions with risks. In this context, the aim of this study is to propose a practical approach that could be utilized to incorporate project complexities in the risk assessment of complex construction projects. The proposed approach entails the integrated usage of risk registers, risk breakdown structures, and complexity-incorporated risk-influence diagrams along with the utilization of a previously developed complexity assessment framework. The underlying basic assumption was that the complexities could directly or indirectly trigger risks, while the risks in turn affect the project objectives. The implementation of the approach in the case of an airport expansion construction project showed that linking the risks to project objectives starting from complexities based on this assumption is possible. In this way, it was shown that multidimensional cause-effect relationships between the complexities and risks, among the risks themselves, and the impact of this interaction on project objectives could be detected and diagrammatically evaluated. Furthermore, it was observed that incorporating complexities in the earlier stages of a project would lead to improvement in the assessment of risks. Considering the results of the case study, the proposed approach has the potential to contribute to improved risk management.