Paillon began climbing in the Alps under the guidance of her mother and her brother, Maurice Paillon. She met Katharine Richardson, an English climber, in 1897 when Richardson was climbing the Meije. They agreed to climb together the next year, and eventually became close friends and frequent climbing partners. In the winter of 1890, together they traversed the Belledonne range in the Dauphiné Alps, and in 1891 they made the first female ascent of the Méridionale d'Arves. They climbed the Meije Orientale with Émile Rey in 1893, marking the third ascent of the peak by women, and Mont Pelvoux in 1897. Following their expedition to Pelvoux, Paillon's eyesight began to deteriorate and she and Richardson retired from serious climbing, since Richardson refused to climb when Paillon could not. The two women subsequently settled together in the Paillon family estate in Oullins.