The observation of neutrino oscillations represents the only experimental evidence for physics beyond the Standard Model. Addressing this issue including right-handed neutrinos generally introduces new sources of CP violation which can be used in the Early Universe to generate a baryon asymmetry, while the sterile states themselves can be a good dark matter candidate. In this talk I will discuss some ideas on how to generate the baryon asymmetry profiting from CP violation in the neutrino sector and a phase transition at the electroweak scale, to then discuss recent developments on the production of sterile neutrino DM from heavier neutrino decays, which represents an irreducible contribution to the abundance when this species is considered as the DM.