Abstract: An abuse-tolerant microwave food packaging material includes repeated sets of microwave energy reflective material segments disposed on a substrate. Each set of reflective segments is arranged to define a perimeter having a length equal to a predetermined fraction of the effective wavelength of an operating microwave oven. The repeated sets of segments act both as a shield to microwave energy and as focusing elements for microwave energy when used in conjunction with food products, while remaining electrically safe in the absence of the food products.