1 Dipartimento di Fisica e Astronomia 'G. Galilei', Università di Padova, Via Marzolo 8, 35131 Padua, Italy ; INFN, Sezione di Padova, Via Marzolo 8, 35131 Padua, Italy.
An overview of the flavour problem is presented, with emphasis on the theoretical efforts to find a satisfactory description of the fermion masses and the mixing angles.