  Flavour physics offers interesting probes for the exploration of the Standard
Model and the search for new physics. In these lectures, we focus on B- and
K-meson decays, introduce the concept of low-energy effective Hamiltonians to
describe them theoretically, and discuss how physics beyond the Standard Model
may generically affect the roadmap of quark-flavour physics. We address then
both the implications of the B-factory data for the B_d -> J/psi K_S channel
and the prospects of B_s -> J/psi phi modes for hadron colliders, and discuss
how the Standard Model may be challenged through B_d -> phi K_S. Finally, as an
example of a systematic flavour strategy to search for new physics, we analyze
puzzling patterns in the B -> pi pi, pi K data and study their interplay with
rare K and B decays.
