She established St Ultan's Hospital for Infants in 1919 and her work in the hospital provides a way of analysing medical politics during a public health revolution in mid twentieth century Ireland. Kathleen Lynn is remembered as a doctor who did her utmost for the poor of Dublin.

Her biography deals with a wide range of issues including: suffragism, education, sectarian politics, maternal feminism, ecclesiastical subterfuge, public health, spirituality, ecumenism, the medical profession and social housing. She is an important figure in international women's affairs as she was to the forefront in new medical practices in Ireland.