2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/47585Recent developments in the theory of weak decays of heavy flavours are reviewed. Applications to exclusive semileptonic B decays, the semileptonic branching ratio and charm counting, beauty lifetimes, and hadronic B decays are discussed.26 pages, 16 figures, uses lamuphys.sty (included); Invited talk presented at the International Europhysics Conference on High Energy Physics, Jerusalem, Israel, 19--26 August 1997High Energy Physics - Phenomenologytext