  The focus of these Lectures is on the weak decay modes of hypernuclei, with
special attention to Lambda-hypernuclei. The subject involves many fields of
modern theoretical and experimental physics, from nuclear structure to the
fundamental constituents of matter and their interactions. The various weak
decay modes of Lambda-hypernuclei are described: the mesonic mode and the
non-mesonic ones. The latter are the dominant decay channels of medium--heavy
hypernuclei, where, on the contrary, the mesonic decay is disfavoured by Pauli
blocking effect on the outgoing nucleon. In particular, one can distinguish
between one-body and two-body induced decays. Theoretical models employed to
evaluate the (partial and total) decay widths of hypernuclei are illustrated,
and their results compared with existing experimental data. Open problems and
recent achievements are extensively discussed, in particular the determination
of the ratio Gamma_n/Gamma_p, possible tests of the Delta I=1/2 rule in
non-mesonic decays and the puzzling asymmetric non-mesonic decay of polarized
hypernuclei.
