The CERN Large Hadron Collider (LHC) is a 26.7 km high-energy proton and ion collider based on several thousand high-field superconducting magnets operating in superfluid helium at 1.9 K. After a decade of development of the key technologies, the project was approved for construction in 1994. Then it took almost 15 years to bring it to operations. In the mean time, a few thousand people were involved in a wide range of activities, from the completion of its R&D program, to its commissioning with beams. The technical expertise of all those who contributed this project were necessarily a key factor to the success of this unprecedented endeavour. But having all these experts working together was quite a challenge also. As from the early stage of this large-scale project, state-of-the-art project management practices were set up. Several of them were certainly crucial for the success of this project, some others certainly much less. This seminar aims at reviewing all the project management practices that were implemented as the project progressed. The Project Management Institutes Project Management Body of Knowledge will serve as a framework for collecting and analysing these lessons learned.