Heavy-flavour phenomenology from lattice QCD

The latest results on several weak hadronic amplitudes that have been computed in numerical simulations are reviewed. Many of these results have already had, or are expected to have, a significant impact on the phenomenology of weak interactions, and in particular on our understanding of CP violation. The main topics discussed in this review are: leptonic decay constants of pseudoscalar heavy-light mesons, B-(B) over bar mixing amplitudes, semi-leptonic decays of D and B mesons, radiative decays of B mesons and the Isgur-Wise function.