Josephine Letitia Denny Fairfield CBE (10 March 1885 – 1 February 1978) - British doctor

Josephine Letitia Denny Fairfield CBE, known as Letitia, was a doctor, a lawyer, a war-worker, and the first ever female Chief Medical Officer for London. She received a CBE for her outstanding achievements in medicine following her contributions during the First World War. 

Despite initially having been rejected by the War Office, Laetitia went on to work for the London County Council, where she campaigned for the initiation of new Public Health departments relating in particular to women's and children's health, and defending who she believed were the most vulnerable members of society. 

When the Women's Army Auxiliary Corps was formed in March 1917, Fairfield was appointed as their Medical Officer. A year later, she was appointed Chief Medical Officer to the Southern Command, and was subsequently elevated to Inspector of Medical Services for the Woman's Royal Air Force.