This article describes results on methane partial oxidation in (La0.6Sr0.4)(Ga0.8Mg0.05Co0.15)O-3 ceramic membrane reactors. The thin membranes were fabricated by co-firing with porous composite NiO-La-doped Ceria (LDC) supports. A La0.6Sr0.4Fe0.2Co0.8O3-based composite layer on the air side of the membrane promoted fast oxygen reduction. Electrical measurements indicated that LSGMC showed good mixed conductivity and that oxygen transport was co-limited by bulk and interfacial processes. The O-2 permeation rate during methane partial oxidation at 750 C was approximate to 10-12 sccm/cm(2), with a maximum syngas production rate of 60-70 sccm/cm(2).