The 23rd Winter school on Mathematical Finance will be held in Soesterberg, the Netherlands, on January 19-21, 2026. Mini courses will be given by Xin Guo (University of California, Berkeley) and Christian Bayer (Technical University of Berlin), on reinforcement learning and rough volatility models respectively. Special invited lectures will be provided by Eduardo Abi Jaber (Ecole Polytechnique, Sorbonne University, Paris), Giorgia Callegaro (University of Padova) and Sigrid Källblad Nordin (Royal Institute of Technology, Stockholm). For more information, see the website.