Accelerators play a crucial role in the physics of the infinitely small, where the goal is to explore new domains of energy (access to new particles) and intensity (access to rare phenomena). All particle accelerators use magnets to transport the beam. All particle physics experiments need large magnets to deduce the properties of emitted charged particles by detecting them. Accelerators and magnets are thus key elements of any subatomic physics experimental program. Irfu’s aim is to be able to make a major contribution to building magnets and accelerators, today and tomorrow, up to and including complete project management for systems or subsystems. This strategy is based on strong collaborations with the best international partners, such as CERN.