This paper presents a digital system for controlling and assessing partnering relations during the carrying out of construction projects, called “B-rel”. The system provides recommendations that can improve specific partnering relations parameters. Its novelty is based on considering how the improvement of individual partnering relations parameters carries over to the time, cost, quality and safety of carrying out a project. The study shows that developing partnering relations in construction projects has the greatest carryover to benefits concerning their time and cost. The system features a learning module and an explanatory module. Thus, B-rel is able to adapt to a specific project and present an inference path that leads to a given recommendation. It can also present saved parameter ratings using graphs. The system's operation has been tested on the example of an actual construction project, demonstrating that the system can successfully support partnering relations management.