Pieter Mattelaer is the Group Leader of the Project Portfolio Management group at CERN, responsible for overseeing all major construction projects across the CERN site. He holds master’s degrees in Civil Engineering from UC Berkeley (USA) and in Architectural Engineering from KU Leuven (Belgium).
Pieter began his career at Arup in London and spent a decade in consulting engineering in the UK and California before joining DEME Offshore, an international EPCI contractor based in Belgium. In 2015, he moved to Switzerland to lead the civil works for CERN’s High-Luminosity LHC project, managing the effort from concept design to completion in 2023.

In his role, he is intricately involved in all procurement and contractual matters on CERN’s construction projects, which are delivered under FIDIC contracts. His professional experience spans the full breadth of the construction sector, with projects both above and below ground, onshore and offshore. He is currently leading the design and construction of two new mixed-use tertiary buildings at CERN in Switzerland and France, one of which will be CERN’s first mass-timber building, now entering the construction phase.