Over millions of years, Australia's unique biodiversity has produced a large cabinet of curiosities. Among the weirder members of this group were the Mihirungs, members of the now extinct family Dromornithidae. Made up of several genera of flightless birds—among them one of the very largest birds that ever lived—the dromornithids ranged from 60-kilogram beasts, 1.5 meters tall, to giants twice that size, weighing nearly half a metric ton. They were, by orders of magnitude, the largest "geese" that ever lived. One species was comparable in size to the Ele-phantbird of Madagascar and the Giant Moa of New Zealand. This book is the first major study of this unique and highly diverse group. It aims to present as complete a synthesis as possible of current information about this fascinating family of birds.