AbstractWhen Australia extended its boundaries by 200 nautical miles, over-night more than three million square nautical miles of undersea territory was placed under its control. This area includes 660,000 square nautical miles of continental shelf, and the whole area to depth requires mapping and exploration.The Australian trained land surveyor, with his special expertise and understanding of this land, and its resources, can readily adapt his training to meet this new survey challenge. It appears that to date very little involvement has taken place by the surveying profession. This article reviews brie~y the most modern survey techniques developed, or being developed, and suggests how the profession as a whole can become involved.