Mortimer is also the first Australian to climb both Everest and K2. He has worked as a geologist, a survival-training instructor, and a Scientific Affairs Adviser for the New Zealand Antarctic Division. He is a geochemist by profession and now runs a business selling adventures to Antarctica and is a motivational speaker. In 1988 he organized the Australian Bicentennial Antarctic Expedition which was covered in two documentaries; 'The Loneliest Mountain', by Film Australia and 'Everest - The Australian Assault', by the Australian Television Channel Nine Network.
His climbing accomplishments aside from Everest include the first ever summit of Annapurna Two via its South Face (1983), the first Aussie summit of Antarctica's highest peak Vinson Massif (1988), and the first Australian ascent of K2, the second tallest mountain in the world (1990). He has been awarded the Order of Australia Medal for mountaineering by the Australian government and has received three Australian Geographic Society medals.
