Boulaz began climbing in the Alps in the 1930s and continued making major ascents until the 1970s. Of her major climbs, four were the first ascents and at least nine were the first female or all-female ascents. At the start of her career, Boulaz and Lulu Durand became the first women to climb the Dent du Requin (1932) and the southwest face of the Dent du Géant. She made a number of climbs with Durand in 1935: the first female traverse of the Aiguille des Grands Charmoz; the first female traverse of Les Droites; the first female ascent of the north face of the Petit Dru (with Raymond Lambert), and the second ascent ever; the first female ascent of the Central Spur of the Grandes Jorasses; the Aiguille Noire de Peuterey; and the Brenva Face of Mont Blanc. She was the first person to climb the east face of the Bel Oiseau (1938), the north face of Mont Vélan (1941), and the Rothorn of Valais (1941). She was the first woman to climb the Pear Buttress on Mont Blanc's Brenva Face (1939), the Walker Spur of the Grandes Jorasses (1952), and the north face of the Cima Grande di Lavaredo (1960).
Outside of the Alps, Boulaz traveled often within the Himalaya, the Caucasus and the Sahara. In 1959, she was a member of the all-female expedition to Cho Oyu where Claude Kogan, Claudine van der Straten-Ponthoz and three Sherpas died during an avalanche. In 1977, she was the first to climb a new route in the Aïr Mountains of the Sahara, which she named Tour Loulou. She was made an honorary member of the Swiss Alpine Club, even though the club did not allow women to become members at the time, as well as holding honorary membership of the Ladies' Alpine Club and the Alpine Club.
Boulaz was also a successful alpine skier; she was a member of the Swiss national ski team in 1936 and 1937, and in 1937 she placed fourth in the FIS World Ski Championships slalom category in Chamonix.
- Roch, André (1993). "In Memoriam: Louise Boulaz 1908–1991". Alpine Journal: 323. Retrieved April 5, 2014.
- Fink, Caroline; Steinbach Tarnutzer, Karin (2013). Erste am Seil: Pionierinnen in Fels und Eis (in German). Tyrolia Verlag.
- Commire, Anne (1999). "Boulaz, Loulou (1912—)". Women in World History: A Biographical Encyclopedia. Yorkin Publications.
- Loomis, Molly (2005). "A Woman's Place is On Top". American Alpine Journal 47 (79): 113. Retrieved April 5, 2014.