Few organisms inspire the superlatives that whales do. They inhabit environments at scales that defy our tools of investigation, and we know little about their natural history and evolution. Sperm whales, the species celebrated in Herman Melville’s Moby Dick, dive over 3,000 meters deep, range from the polar seas to the tropics, and live in matrilineal clans. Rorquals, such as blue whales, feed by engulfing huge mouthfuls of prey-laden water. Like rorquals, right and bowhead whales undertake vast oceanic migrations. The Great Whales -- sperm whales, rorquals, and right and bowhead whales -- comprise a non-natural group of cetaceans united by extremely large body size (up to 30 meters long and 150 tons in weight) and a history of human hunting. Fundamental knowledge about them is tied to episodes of whaling; today they are icons of conservation. Several advancements and new knowledge have led to the need for a synthesis of their ecology and evolution. How do they feed, communicate, and move across oceans? How did their unique traits and large body size evolve? This symposium aims to answer these questions on the basis of fields as disparate as acoustics, biomechanics, historiography, and paleontology. Great Whales appeal to the general public and media; therefore, each talk will address their evolution and current status as survivors of a near-mass extinction caused by humans. The symposium discussion will draw conclusions about the evolutionary processes that gave rise to these giants and their future.