The fourth edition of the Swiss Quantum Days took place at the Hotel Terrace in Engelberg in canton Obwalden from 28-30 January. The event was co-organized with the Swiss Quantum Initiative, Geneva Quantum Centre (GQC), EPFL Center for Quantum Science and Engineering (QSE), Quantum Center, ETH Zurich and NCCR SPIN: Spin Qubits in Silicon. We welcomed our keynote speaker professor Jun Ye from JILA/NIST in Colorado who held a talk about "Quantum engineering for practical advantages in clock".
We enjoyed inspiring talks by BQC Prof.Tomasz Smolenski, BQC researchers Alvaro de Melo, Jodok Happacher, Arianna Nigro, Timon Baltisberger and Aaron Daniel and poster session contributions.

The first edition of the Swiss Quantum Winter School preceded the Swiss Quantum Days. Around 40 participants from across Switzerland attended the winter school, most of them first- and second-year PhD students.