Charis met Dorothy L. Sayers whilst studying at Somerville College, Oxford, and became one of the six women who founded the writing group the 'Mutual Admiration Society'.

All six members remained lifelong friends, as they each sought to further the rights of women in several different ways. For Charis, this meant being a pioneer in the fight for reproductive rights, as she co-founded one of the country's first birth control clinics in Salford in 1926. She also frequently had letters to the editor published in the Manchester Guardian about motherhood and access to birth control for women.

Charis published several books on child-rearing which include:

Common Sense in the Nursery (1913)
Latin with Laughter (1930)
I'm All Right, Or, Spoilt Baby Into Angry Young Man (1960)
Common Sense about Children: A Parents' Guide to Delinquency (1973)

She also wrote an autobiography:
Not Old, Madam, Vintage (1975)

Charis’ brother Denis was due to join his sister at Oxford in the autumn of 1914, but this was put on hold to enlist in the army.

Faced with the prospect of returning to Oxford without her brother, Charis immediately applied for leave from Somerville to undertake war work. “The men did, and why shouldn’t I? And the principal said, right you are, bless you and go.” Charis’ situation was unusual; the university generally encouraged its female students to remain at their studies. This would keep the university going and assist in helping women students qualify for teaching as a form of national service, to make up for the shortfall in male teachers.

Denis’ death in August 1915 pushed Charis to want to do war work in France. She had been doing all sorts of work with the Women’s Emergency Corps and the Women’s League of Service since 1914, including interpreting and working at an infants’ clinic. After her brother’s death she visited the Friends War Victims Relief Committee, because she heard they were sending people to the continent, and they advised her to train as a midwife.

She went off to Dr Annie McCall’s Clapham Maternity Hospital to receive her training, and then arrived in France as a fully certified midwife in October 1916. She spent most of October working at a convalescent hospital in Samoens. Once her war zone permit came through, Charis continued onward to the maternity hospital at Chalons-sur-Marne, where the Friends were caring for Belgian refugees.

War work was frequently, for young women, interrupted by family duties. Charis had to suspend her war work to return home and help her mother care for her Aunt Louie in March 1917.