As a part of supply chain management (SCM) initiatives to improve performance and productivity in construction projects, the use of construction logistics setups (CLSs) operated by third-party logistics (TPL) providers have increased. CLSs are often used in complex multi-project contexts, such as urban development districts, where extensive coordination of actors, resources, and activities is needed. The purpose of this paper is twofold: to investigate how main contractors engage in horizontal relationships with each other when coordinating activities and resources within and across projects in a multi-project context, and to investigate what role a TPL provider assumes when engaging in relationships with main contractors in a multi-project context. The findings are based on a case study of an urban development district with a mandatory TPL-operated CLS, and we apply the industrial network approach. In this multi-project context, the main contractors engage in coopetitive relationships, coordinating activities and resources within and across projects. The TPL provider coordinates actors, resources, and activities, facilitating smoother production by managing logistics and mediating coopetitive relationships. This can be understood as a multi-project coordination role and extends the role SCM can play in construction. In that role, a TPL provider can minimise tensions between coopetitive actors across a multitude of horizontal relationships and projects.