From 1939, Dot spent three summers in New Zealand. Her work as a guide in the Mt Cook National Park was an important influence on her post-war activities. During this time, she met the young Edmund Hillary, and climbed the Remarkables, only donning boots for the portion of the climb in snow and ice. In 1940, she became a member of the New Zealand Alpine Club, being elected on her first attempt. In 1941, she climbed New Zealand's highest peak, 3,763 metre high Mount Cook.