CP violation in B decays

The experimental study of CP violation in B decays has led to significant progress in our understanding of nature: (i) It demonstrated that the Kobayashi-Maskawa mechanism is the dominant source of CP violation in meson decays. (ii) It improved significantly the precision in the determination of the parameters of the Cabibbo–Kobayashi–Maskawa quark-mixing matrix. (iii) It proved that new physics that has order-one flavour-changing couplings to the b quark should be characterised by a mass scale higher than O(10³ TeV). Further progress is expected from the Belle II and LHC experiments during the next decade and beyond. Present status and perspectives are here discussed.