Metallicity dependence of light and heavy s-process elements in AGB stars.

The s-process in AGB stars is far from being a unique process. Observations of s-enriched stars indicate that a multiplicity of neutron exposures are needed at each metallicity. Model predictions of AGB stars of different metallicity, initial mass, and different ¹³C-pocket efficiencies, are presented and discussed, pointing out in particular their ability to reproduce the range of observed s-process elemental distributions in very metal-poor C-rich and s-rich objects.