The study looked at what makes road construction projects complex from different viewpoints. Industry experts shared their opinions on the most important factors at each stage of a project. The main complexity measures included design buildability, cost constraints, technical aspects, environment, and project urgency. Key stages like project conception and construction were highlighted as crucial for managing stakeholder expectations and risks. The project owner was found to be the most influential stakeholder. Good communication was seen as vital for maintaining relationships with stakeholders throughout the project.