We present the latest Belle II and Belle results on rare B decays, based on data samples of 365 and 711\, fb^-1, respectively, collected at the (4S) resonance. Rare B decays, in particular flavor-changing neutral currents (FCNC) of the type b s, provide unique sensitivity to a wide range of new-physics scenarios. Belle II and Belle are achieving world-leading precision and are probing intriguing anomalies in B^+ K^+ that have generated broad interest within the particle-physics community. We discuss several new FCNC measurements, as well as results on B^+ ^+ _, which set the current most stringent limits on branching fractions and impose new constraints on theoretical models.
C. Schmitt (Fri,) studied this question.