This paper evaluates the benefits of polycarbonate resin as a structural layer in high-barrier coextrusions for flexible packaging. High-temperature performance requirements are examined for hot-fill, retort, autoclave, and ovenable packaging. Coextrudable barrier resins and tie layer resins are evaluated for processability, and the benefits of low- and high-moisture barriers are compared in composites using moisture-sensitive oxygen barrier resins. Optimum barrier composite structures are defined and evaluated.