This is the third volume in The Australian Centenary History of Defence series. This volume, written by a team of leading naval historians, offers a penetrating analysis of the Royal Australian Navy in the twentieth century. More than a chronicle of naval activities, it explores the effects of changing strategic circumstance, technological innovation, and differing national needs and expectations. Reviewing Australia's naval involvement in operations that have ranged from global war through to peacekeeping and natural disaster, the authors explain how the Senior Service developed from a collection of colonial gunboats into a vital element in today's national defence.