In 1913, Ardill completed a one-year internship at the
Prince Alfred Hospital and served as an honorary anaesthetist and out-patients medical officer at the South Sydney Women's Hospital. Ardill therefore travelled to Britain, signing up with the British Red Cross who in September 1915 deployed her to serve at the Anglo-Belgian Hospital in Calais. In mid-1916, Ardill become one of the first women doctors in the
British Expeditionary Forces field services, when the army changed their policy to allow the to enlist on a contractual basis. Serving under the
Royal Army Medical Corps, Ardill was deployed to the County Middlesex War Hospital,
St. Albans, England. This was previously an asylum, but in September 1915 it was reopened as a hospital to treat wounded soldiers as they arrived from the
Western Front, and had 1600 beds and the capacity to treat 250 men in its specialist military mental health unit. She then worked at the Anglo-Belgian Base Clearing Military Hospital at
Étaples in France, and was later promoted to the rank of captain. == Awards and honours ==