A packaging method is proposed in which two substrates 23a, 23b, each carrying at least one die 21a, 21b, are placed back-to-back in a mold chase 22 with their surfaces 20a, 20b, which carry dies, facing into respective cavities 24a, 24b. Each cavity is fed liquid resin through at least one respective channel 28a, 28b that introduces the resin into the cavity at a location spaced from the corresponding substrate. Thus a resin body 29a, 29b is formed on each of the substrates 23a, 23b. Thus, a package is produced from each of the two substrates 23a, 23b in a single molding operation. The invention is particularly suitable for producing flip-chip-in-package type packages.