We review recent results of Lattice QCD calculations relevant for flavour
physics. We discuss in particular the hadronic parameters entering the
amplitudes of K0-K0bar, D0-D0bar and B0-B0bar mixing, the B- and D-meson decay
constants and the form factors controlling B-meson semileptonic decays. On the
basis of these lattice results, which are extensively collected in the paper,
we also derive our averages of the relevant hadronic parameters.Comment: Plenary talk at IFAE 2008, Bologna, Italy, 26-28 March 200