Abstract high barrier packaging applications for medical, industrial and food packaging often include aluminum foil. Thinner gauges of aluminum foil contain pinholes through which moisture and oxygen from the environment can enter the package accelerating the degradation of the contents. This paper addresses the impact of foil pinholes and fractures on the oxygen and moisture barrier of multilayer flexible packaging, in theory and in practice using laserproduced pinholes. The analysis shows that the transmission through the pinholes is less than that occurring through exposed sealant edges and much less than that which would take place through nonfoil packaging of the