Collaborative delivery methods in construction projects provide a new operational environment, which can foster effective interaction and cooperation between different project stakeholders. Project managers are one of the most important players in this environment, who therefore need to possess appropriate competencies. Collaborative construction projects and their managerial solutions are still a relatively new field and, thus, special aspects such as competencies of project managers in such projects have been limitedly studied. The present research aimed to evaluate project managers’ competencies in collaborative construction projects in Finland through a human behavioral approach, where project managers’ everyday work was the main source for understanding the competencies of relevance. Accordingly, a web-based questionnaire and semi-structured interviews were used for data collection from the case projects. Based on the gained data, project managers’ behaviors were analyzed, and consequently, their specific competencies were identified. Findings of this study propose 10 core competencies for project managers in collaborative construction projects, e.g., group capabilities, language proficiency, and leveraging diversity. Additionally, a set of supportive competencies were identified which, together with the core competencies, form the profile of project managers’ competencies for collaborative construction projects. Finally, the differences between competencies needed in traditional and in collaborative construction projects are discussed.