Block copolymers containing polyester and polyamide blocks have been prepared by the bulk reaction of the corresponding carboxy-terminated polymers with 2,2’-bis(2-oxazoline) or 2,2’-bis(5,6-dihydro-(4H)-1,3-oxazine) as chain-coupling reagents (CC). A two-step reaction has been used, involving (i) the reaction of polyamide with CC excess, and (ii) the addition of polyester, leading to a random distribution of blocks in the final block-copolymer. H-1 and C-13 NMR studies show that the coupling reaction takes place in the expected way. The stability of the resulting polymers is higher than that of the starting oligomers, and DSC indicates a phase separation between polyester and polyamide phases.