  We study thermal leptogenesis in classes of neutrino mass models based on the
seesaw mechanism with three right-handed neutrinos and sequential right-handed
neutrino dominance. The flavour-dependent Boltzmann equations are solved
appropriate to both the Standard Model and the Minimal Supersymmetric Standard
Model. Within these classes of models we investigate constraints and
expectations on the individual decay asymmetries and washout parameters from
the present data on neutrino masses and mixings. In many cases of physical
interest flavour effects are shown to have important consequences for the
estimation of the produced baryon asymmetry in leptogenesis. We also establish
and analyze the link between the leptonic CP violating phase $\delta$,
observable in neutrino oscillations, and the CP violation required for
leptogenesis, where flavour-dependent effects have a significant effect. In
general our results show that flavour-dependent effects cannot be ignored when
dealing with three right-handed neutrino models.
